Limited Lifetime Warranty.

We will replace, or refund the cost of, any properly deployed Ursack in which a gap, tear or hole larger than 1/4 inch is caused by a bear, if an S29 AllWhite, or a critter, if an Ursack Minor (i.e we do not warrant against critter damage to a S29 AllWhite). This 1/4 inch standard is the criteria used in Interagency Grizzly Bear Committee’s test protocol. We ask that customers return any damaged Ursack to us for inspection.

Unused bags in brand new condition may be returned for a full refund – less shipping charges and a handling fee – within 30 days of purchase.

After that there is no refund (except for warranty reasons). This policy is strictly enforced. We do not give refunds because a particular wilderness area or National Park changes its policy on Ursack. If you would like to make a return please email us first for return merchandise authorization (RMA)

Sorry, but we have no control over Park policy.

Limited Lifetime Warranty.

We will replace, or refund the cost of, any properly deployed Ursack in which a gap, tear or hole larger than 1/4 inch is caused by a wild animal. This 1/4 inch standard is the criteria used in the Interagency Grizzly Bear Committee’s test protocol. We ask that customers return any damaged Ursack to us for inspection.

Standard Shipping.

Generally sent 1st class mail and should arrive within seven days.

Expedited Shipping.

Orders that we receive Monday-Friday before 12:00 noon ET/9:00 a.m. PT, will be shipped the same day by Priority Mail. Orders that we receive after 12:00 noon ET/9:00 a.m. PT on a business day, or on a weekend or holiday, will be shipped the next business day after the order date.

Two Day Shipping.

Orders that we receive Monday-Friday before 12:00 noon ET/9:00 a.m. PT, will be delivered within two business days after the order date. Orders that we receive after 12:00 noon ET/9:00 a.m. PT on a business day, or on a weekend or holiday, will be delivered within three business days after the order date.

Privacy Policy/Terms and Conditions

URSACK, Inc. does not share, rent, sell or trade e-mail addresses or information. URSACK, Inc. does not share any personal information or financial information for any purpose other than to verify credit card orders to verify your order.

Information Collection and Use URSACK, Inc. is the sole owner of the information collected on this site. We will not sell, trade, share, or rent this information to others in ways different from that disclosed in this statement. URSACK, Inc. collects information from our users in several different ways on our website.
Order We request information from the user on our order form. Here a user must provide contact information (like name and shipping address) and financial information (like credit card number and expiration date). This information is used for billing purposes and to fill customer’s orders. If we have trouble processing an order, this contact information is used to get in touch with the user. A user may choose to register to receive e-mail and printed newsletters and marketing materials from URSACK, Inc.. During registration a user is required to give his/her contact information, such as name and email address, so that URSACK, Inc. can provide the desired service(s).

Cookies A cookie is a piece of data stored on the user’s hard drive containing information about the user. URSACK uses cookies only to identify each user’s session. If a user has supplied personally identifiable information as part of the ordering process, then the cookie can be linked to such information. However, once the user closes their browser, the cookie simply terminates. Completion of an order also causes shopping cart data to be removed from the web site. For instance, by setting a cookie on our site, the user could interrupt the ordering process with visits to non-related sites without losing his/her shopping cart data. If a user rejects the cookie, they may still use our site. The only drawback to this is that the user must be careful to return to the Ursack.com website via the “Back” button on his/her browser after visiting non-related sites.

Log Files We use IP addresses, dates, times, document requested, referring address and user agent to analyze trends, administer the site, track user’s movement, and gather broad demographic information for aggregate use. IP addresses are not linked to personally identifiable information.

Sharing We do not share information. We use an Internet hosting company for Ursack.com. This company does not retain, share, store or use personally identifiable information for any secondary purposes.

Links This web site contains links to other sites. Please be aware that URSACK, Inc. is not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects personally identifiable information. This privacy statement applies solely to information collected by this website.

Newsletter and E-mail Advertising If a user wishes to subscribe to our newsletter and receive e-mail advertising, we ask for contact information such as name and email address.

Security This website takes every precaution to protect our users’ information. When users submit sensitive information via the website, their information is protected both online and off-line.

When our registration/order form asks users to enter sensitive information (such as credit card number and/or social security number), that information is encrypted and is protected with the best encryption software in the industry – SSL. While on a secure page, such as our order form, the lock icon on the bottom of Web browsers such as Netscape Navigator and Microsoft Internet Explorer becomes locked, as opposed to un-locked, or open, as when you are just ‘surfing’.

After order forms are submitted, the data is encrypted using the SSL program and sent to URSACK, Inc. The sensitive data is then removed from the Website.

While we use SSL with 128 bits to protect sensitive information online, we also do everything in our power to protect user-information off-line. All of our users’ information, not just the sensitive information mentioned above, is restricted in our fulfillment center and offices. Only employees who need the information to perform a specific job (for example, our billing clerk or a customer service representative) are granted access to personally identifiable information. Furthermore, ALL employees are kept up-to-date on our security and privacy practices. Finally, the Internet servers that we store personally identifiable information on are in a limited access environment at out hosting company’s facility. If you have any questions about the security at our Website, you can send us an email.

Special Offers Customers and those who register to do so will occasionally receive information on products, services, special deals, and a newsletter. Out of respect for the privacy of our users we present the option to not receive these types of communications.

Fulfillment and Comments We communicate with customers to resolves issues that arise in connection with completing orders or in response to comments submitted during registration or via e-mail. We communicate with the user to provide requested services and in regards to issues relating to their account via email or phone.

Notification of Changes If at any time we change the manner in which we use personally identifiable information from that stated at the time it was collected, users will have a choice whether or not we use their data in this different manner. Before we use their data in this different manner, we will notify users of the change via e-mail and give them that option to opt-in. Unless a user agrees to the change, will use his/her information in accordance with the privacy policy under which the information was collected.


Do the National Park and Forest Services accept URSACK as an alternative to hard-sided, bear-proof containers?

There is no uniform testing or approval mechanism for the National Park or Forest Services. However, many areas have assigned testing to the Interagency Grizzly Bear Committee (IGBC). In 2014, the Ursack S29 AllWhite (a/k/a S29.3 AllWhite) passed the IGBC test and has been given certification number 3738. In 2017 , the Ursack AllMitey passed the test and was given certification number 5135. In 2014, at IGBC insistence, we baited an Ursack S29 AllWhite, knotted it securely and placed it on the ground with no aluminum liner and not tied to a tree. The first two grizzlies went at it for an active 57 minutes. One of the bears was nick-named “The Destroyer,” but neither he nor his sister were able to compromise the Ursack. The Grizzly Wolf and Discovery Center rotates bears in and out at approximately one hour intervals. So the Destroyer went back to his quarters and five, count ’em, five more grizzlies came out to work on the same Ursack. The IGBC testing protocol requires a total of 60 minutes of active bear encounters, so even though we needed just a few minutes more to pass the test, there was no way to get the Ursack out until the five bears finished their shift. Not to worry. Ursack made it for another hour. A total of seven grizzly bears and two hours of active clawing, biting and scratching–yet Ursack survived. After washing the Ursack one could barely (bearly?) tell that it had been attacked. Every park has its own standards for acceptable bear and critter resistant containers. For example, Canyonlands, Glacier and Mount Rainier National Parks have all purchased Ursacks, while other National Parks restrict or ban the use. Some parks require bear-resistant containers, but do not specify any particular brands. The most accurate information is usually on their websites. Sometimes rangers do not know the current rules. For example, Inyo National Forest has, by Forest Order since about 2009,  required that in certain areas “food or refuse [be] stored in a container designed to prevent access by bears.” Inyo considers Ursack to be such a container if counter-balanced although that is not written anywhere (except in emails from officials there). There have been reports that some rangers do not always know this, and tell campers that Ursack is not allowed. Some areas, e.g. Yosemite, SEKI and the neighboring Toiyabe National Forest, specifically list the allowed containers. Ursack is currently not on that list although it is being considered.

Always contact the Park or Forest you will be visiting BEFORE you bring Ursack (or any other container). You can avoid our restocking fee by checking first.

Here is a link to food storage requirements in Grizzly country: http://igbconline.org/food-storage-regulations-2/.

Is Ursack resistant to raccoons, rodents, marmots, wolves, etc?

The AllMitey is. Generally speaking, the Ursack S29.3 AllWhite is highly effective against marmots, raccoon and other critters. It is important to note that different parts of North America have different species of rodents.

We like this report from Alaska in 2008:

The Ursack has performed well in the forest and on the beaches. More to the point of this thread, it has beat the most voracious Forest Service cabin vole. No other, “critter” that I know has the tenacity and the motivation to extract food from a bag than the vole. It lives on its own for five days of each winter week and then is provided ample opportunity to gorge itself on Friday and Saturday nights. The Ursack stands the test of the Grizzly and the mighty vole.

In almost every case, a marmot or raccoon won’t tear a hole (more than 1/4″) or get your food, but their claws and teeth may puncture the Ursack and the food inside.  To eliminate the risk of punctures add an aluminum liner. If then hung from a tree, the only vulnerable spot would be the top of the Ursack and there is not much risk there because the fabric is thicker at the hem and the food sits lower because of gravity.  To avoid risk altogether you could put an aluminum or titanium plate on the inside top.

Ursack should not be considered wolf or dog resistant. That’s because canines have sharp teeth and strong jaws. Bears have great strength, but their teeth are not sharp. We now make a rodent resistant bag, the Ursack Minor. It is not effective against bears although we think it may be more effective against rodents than the AllWhite. Other rodents have varying degrees of success. Sometimes mice can chew very small holes, but very little of your food is likely to be taken. Some species of squirrels and (we have heard) pine martens have greater success, and may on rare occasion chew holes in bear resistant Ursacks. Our newest AllWhites, made since about April 1, 2015, have a tighter weave and more than double the tear strength compared to previous models. Dubbed the S29.3, it has an excellent record against critters.

Punctures, which are typically just weave separations, will easily wash out. Machine wash, no bleach, line dry.

Can I wash my Ursack? How can I rethread the cord?

Yes. At home: All Ursacks except the AllMitey can be machine washed with cold water, use detergent but no bleach, line dry. Tie a knot in the cord first so that it doesn’t come out while tumbling. The AllMitey should be hand washed in cold water. In the wilderness: rinse, then line dry. If your AllWhite has been attacked by a wild animal, washing (especially machine washing) will remove most, if not all, of the weave separations.

If the cord comes out:  Look at the hem/sleeve at the top of your Ursack. Notice there are two pairs of eyelets. One pair (A) is open only to the inside, the other pair (B) goes completely through the hem/sleeve. You can see through B, but not A. Thread cord through one of the A eyelets pass it around through the hem/sleeve until it emerges from the other A eyelet. Cross the cords and push one end of each through the B eyelets.

What does URSACK mean? How is it pronounced?

Ursack: from the Latin “Ursa” for bear and the English “sack” for sack. Rhymes with “purse sack.”

How can I tell if my Ursack is sewn with Spectra thread?

IGBC certification applies only to bags made after April 1, 2014 even if earlier models were sewn with fewer rows of Spectra thread. S29 AllWhites without sewn grommet holes are made with Spectra thread. S29s made before April 2013 (which may or may not have come with SeamGrip) have sewn grommet holes and are not sewn with Spectra thread. About 90 S29s sold in April 2013 have sewn grommet holes but also have Spectra thread. Some green Ursacks made in approximately 2004 were also sewn with Spectra thread. After that we were no longer able to get that thread or the fabric because the military requisitioned most of the available Spectra.

How can I cinch my Ursack completely tight?

For any model Ursack (except the Minor) use leverage if necessary–wrap cord around a solid object and pull against it. Always eliminate any slack in the cord or gaps in Ursack’s closure. Always tie a knot that a bear cannot untie. Directions: If not already laced, cross the cords once so that they form an X before emerging through the eyelets. Pull cords tight one at a time to eliminate any gaps in Ursack’s closure. Then, tie a double overhand knot: Hold the cords so that one end is in each hand. Cross the right cord over the left cord and pull through the loop that has been created. Before cinching, wrap the right cord over and through the loop again. Pull the knot tight. Work the cords so that the knot constricts around itself. The knot must be tight, and there must be no gaps in the closure. Keep bears out! Stop bears from using teeth and claws to untie the knot. Best way: Where allowed, tie the loose cord ends snugly around a tree branch or other fixed object. Otherwise, tie more knots over the first one. Bears don’t have prehensile thumbs. Use yours.

This is what it looks like with no gaps:


Where can Ursack be used on the Pacific Crest Trail?

Ursacks are allowed almost everywhere except (unless changed in 2018) Yosemite N.P. and three areas of SEKI! By our rough calculations, only about 40-50 miles of the 2,650 mile trail is through areas in which an approved bear canister must be used. That is less than 2% of the PCT. The Forest Service Order for Inyo National Forest for 2009 allows Ursacks provided they are counter-balanced in restricted areas. It says: food must be stored in a container designed to prevent access by bears. In the past, Inyo has specified only SIBBG approved containers. That is no longer the case. In addition, there are Park supplied food storage lockers at several locations in the Sierra. See http://climber.org/data/BearBoxes.html. Remember, it is not illegal to hike anywhere with an Ursack. Only camping in a restricted area without an approved bear-resistant container (or food locker) is prohibited.

What is the difference between an Ursack TKO or V27 or S29 and the current model? Why did you change the color from green to white?

In order to avoid confusion, we have renamed Ursack models by reference to the specific fabric they are made with. The original TKOs were made with a lighter Spectra (Green with white ripstop) and then replaced with heavier Spectra (Green–no ripstop–gusseted bottom)in 2004. That fabric became available again and the green Ursack made with that fabric is called S29 (Spectra 29 yarns per inch). Our (yellow) Vectran models were called the TKO 2.0; it is now called the V27 (Vectran 27 yarns per inch). The S29 AllWhite is Spectra, but there is no green coating. Spectra cannot be dyed. Its native color is white. We used to coat it green, but that added weight and made it harder to cinch tight. Ursack is washable.

Won't a bear carry the Ursack away if it is not tied to a fixed object?

Probably not. The SIBBG rangers tested the Ursack Hybrid in both the summer of 2004 and 2005 to see whether a bear would carry it away. They even put a tracking device in it as part of the testing procedure. The results, so far, are that bears are leaving Ursacks very close to where they found them.

Where there are no trees available, try hiding your Ursack under a pile of rocks. If you are using an OPSak and have been meticulous about keeping food smells off the outside, it is unlikely that a bear can find a well hidden Ursack.

What were the results of the Sierra tests in 2004?

SIBBG conducted an exhaustive wilderness study of 15 Ursack TKOs in the summer of 2004.
Despite numerous bear encounters, no bears or marmots were able to access food from an Ursack.

SIBBG, through wildlife ecologist Harold Werner, produced a 20 page single spaced footnoted report accompanied by hundreds of photographs and field notes.

What assembly is required to create an Ursack Hybrid?

You will need to squeeze the aluminum liner into your Ursack and push it to the bottom.
You will know that you have done it right if you are able to cinch the opening of the Ursack completely with no gaps.

Does the Ursack Hybrid need to be tied to a tree branch? How do you counterbalance?


Although we still strongly recommend counter-balancing or tying Ursack to a tree branch, the Ursack Hybrid can simply be placed on the ground like any canister. In grizzly country this is not advised. Be sure to cinch the opening completely; then tie a double overhand knot plus a few more knots that a bear can’t untie. For instructions on counter balancing go to: http://www.nps.gov/seki/planyourvisit/bearhang.htm.

Will the aluminum liner bend?

The aluminum liner is designed to bend but not break. It is possible that a bear might bend the liner out of shape, but even then your food should survive just fine. The liner can be reused although it may have to be reworked into a cylinder shape.

If Ursack is so great, why do I need an aluminum liner?

Ursack is all about light weight alternatives.

For maximum weight savings, use the Ursack by itself. Our Field Test page has a number of reports from those whose food survived bear attacks with little impact. But there is clearly a risk that food carried in an Ursack without a liner will get crushed. The Ursack S29 weighs about 7.3 ounces.

The aluminum liner adds about 10.8 ounces. Together, the Hybrid is lighter than any bear canister on the market. You decide how light you want to go. If a bear should happen to tear the aluminum (we don’t think this has ever happened to a customer), please be sure not to eat the metal pieces.

Will the Aluminum Liner fit in older model Ursacks?

Maybe. It is 8 inches in diameter and 12 inches tall. The liner may require trimming to fit in Ursacks with a sewn bottom (as opposed to gusseted). All kevlar models and most spectra with ripstop models had a sewn bottom.

What if there aren't any trees nearby or you are above treeline?

Cinch Ursack closed using a double overhand knot as shown on the seam label. Then, tie a lot of other knots on top of that so that a bear can’t untie them all. If possible, tie Ursack to any object that is too heavy for a bear to easily drag away.

Where there are no trees available, try hiding your Ursack under a pile of rocks. If you are using an OPSak and have been meticulous about keeping food smells off the outside, it is unlikely that a bear can find a well hidden Ursack.

We used to think that, if possible, use a rock-climbing aid wedged into a crack high up on a rock, then tie Ursack to the aid. Since we thought bears couldn’t climb rocks, this should be very effective. We have never had a report of an Ursack being lost to a rock climbing bear, but this video makes us think that anything is possible.

Do you recommend tying a figure 8 knot above the slider (older model Ursacks) when the bag is cinched? Or only on the lengths going around the branch?

Tie a secure knot (like a surgeon’ knot) above the slider, then take the long loose ends and tie them in a figure 8 around a tree branch. It is important to take away slack in the cord.
We recommend a figure 8 knot around the branch because it is easy to untie even after Ursack has been pulled on by a 500 pound bear.

Can a bear chew through the cord?

No. We have never had a confirmed report of a bear chewing through or breaking the cord.

Have there been any failures?

We have sold bags in 50 states, Canada and assorted foreign countries. So far, there have been very few reports of a bear compromising IGBC approved Ursacks, and no reports of AllMitey failures in real world conditions. A few (about 2 per year) earlier (pre 2014) S29 AllWhites sewn without Spectra thread had the seams ripped. The S29 (green, no ripstop, heavier fabric) introduced June 1, 2004 was the model tested by SIBBG. The fabric has been nearly perfect, but user error (not cinching and knotting Ursack tight) resulted in a few bear incidents. That’s why we changed the design in the AllWhite: to make the cinching and knotting easier.

There is no such thing as a bear proof container. Rangers have reported to us that even the hard sided canisters are broken by bears on occasion. A recently published book, Speaking of Bears, reported that one Yosemite bear rolled about 25 canisters over a cliff to break them on the rocks below. See Update for a longer discussion of canister failures in Yosemite.

Won't my food be squashed or punctured?

With an URSACK Hybrid it won’t be squashed or punctured. If you use Ursack without the Aluminum Liner, probably some, but not all, of your food will be crushed or tampered with. Although we can’t promise that you will have the same results, look at this video showing that food can survive a bear attack unscathed: Bear in Camp: How Did the Ursack Perform

However, substantially packaged freeze dried foods and similar items should still be edible. They are pre-squashed anyway and boiling cooking water should eliminate contamination risks.

Worst case : you will eat nutritious mush.
Best case : you will not have to carry nearly three pounds of a bulky, hard-sided canister.

Some people carry both URSACK and a canister, keeping their most precious items in the canister, and reserving URSACK for expendables and garbage.

Will I be able to untie the cord after a bear pulls on it?

If you follow the directions and use a figure 8 knot to secure URSACK®, you should be able to untie the knot even after a bear has yanked on it. Take a look at the bear test video at the Grizzly Discovery Center in May 2013. A number of bears attacked the Ursack for an hour and we were able to untie it from the tree and untie the closure without using any tools.

Worst case: although the cord is highly resistant to chewing, you can cut it with a very sharp knife.

Does the OPSak require special handling?

Please use care when packing the O.P.SAK to avoid pulling the seal off the film. It is also important not to over stuff or force the O.P.SAK to close. When possible, leave the O.P.SAK inside your Ursack and retrieve your food without removing the O.P.SAK. This will prolong the life of the O.P.SAK and will also help keep food smells from your hands off the bag. O.P.SAKS should be replaced after extended use.

Is Ursack waterproof?

Standard Ursacks are not waterproof. The laminated AllMitey is waterproof except the seams, which should be sealed for water resistance. The fabric in standard Ursacks will not absorb water, but the weave is loose enough to allow some water intrusion. The opening cinches very tightly but not enough to be waterproof. However, the optional odor bag, OPSak, is waterproof. As long as you use the odor bag your food will stay dry and you can wring out whatever water clings to the Ursack itself.

Should I buy an Ursack S29 AllWhite or an Ursack Minor?

The AllMitey resists both bears and critters. If you choose not to purchase an AllMitey, then if you will be camping in bear territory, buy an AllWhite. If not, save money and weight and buy a Minor. The new AllWhite, made since about April 1, 2015, has increased tear strength and a tighter weave compared to previous models. It is highly critter resistant.

Do you accept mail orders?

Yes we do. Send them to:

Ursack, Inc.
38 Miller Ave. #488
Mill Valley, CA 94941.

Please add $6.95 for shipping. We have no inventory in Mill Valley