LOKSAK  OPSak Odor-Proof Barrier Bags - 20 x 12.5

I tested this bag before using in the backcountry. I put catnip in it and left it on the living room floor all day. My cat, who is usually crazy for the stuff, never showed the least bit of interest. So I took it on a 3 day backpack in the Cascades. Kept it in a stuffsack to protect it and hang it. Had no problems. On the last day I just put in the ground, very far away from my bivy. No nibbles! Thank god I don't have to use that heavy cannister anymore! BUT .... it is a realy pain to seal the thing. It seems like it should be an easy zip-lock, but its not. You have to be very precise and double check it to make sure its really sealed.

I´ve used OP Saks on thru-hikes of both the Continental Divide Trail (2,800 miles) and Pacific Crest Trail (2,650 miles) and have never had a bear, rodent or any other animal get my food or even try. These OP Saks work! They don´t last forever, but they work. You can quadruple bag ziplocs but they will not be odor proof - OP Saks are truly odor proof. If you overstuff them, they will break so don´t overstuff them. Carry 2 instead. They also work well to wash trail-travel clothes in with a few drops of liquid soap. Just seal in the clothes, water, soap and shake! Bottom line is that they do exactly what they say they are supposed to do - keep odors contained.

I use these to keep food and garbage odors to themselves and away from bears. These lasted a week on a backpack trip with some care in handling. I bought new ones for the next trip, just in case. Because they do their job well, avoid putting strong, contrasting items in the same bag. Your minty fresh gum will infuse your snack crackers and your spicy pasta sauce will flavor your cookies if you put them in the same bag. I recommend one for trash, one for strong-odor foods, and one for mild foods.

A friend of mine had these on a hike. How do I know? Because my hound dog sniffed them out in seconds. The thing is with foodstuffs, it doesn't matter how good the outer seal is or the material of the bag... If you get food on your hands and then touch the bag, say to seal it, the odor on your hands will be on the outside of the bag. It only takes 18 ppm for an animal to be able to smell something. Some animals can smell in parts per billion. Please do not use these bags and think you don't have to hang your food or put it in a canister- for safety's sake, ALWAYS handle food carefully.

I first purchased and used the Loksak a year ago for a week-long trip into the San Juan Mountains in SW Colorado. For another similar trip a couple of weeks ago, I couldn't find the one I used last year (probably under a pile of gear somewhere), so I purchased another. In both cases, I used the Loksak in conjunction with the Ursack bear resistant bag and hung all food - although not high enough that bears would not have been able to reach it. My hiking partner also used the Loksak but with a regular stuff sack for hanging. We saw bear scat not too far from our camp, but we had ZERO problems with bears or any critters getting into our food or creating hazards due to being attracted by food. My partner did have a marmot chew up some of his gear, but that was unrelated. We also saw a porcupine in camp, and heard hooved animals roam through camp at night. All in all, I'm pretty happy with the outcome.

I have had these bags for a few months now and used them on a few overnight trips. They seem to be fairly durable but I am careful not to put anything too pointy in them. As long as you are careful when sealing them up the seal isn't an issue and the odor is blocked. I think the best test of this is on a recent trip we made a curry rice. You could smell the curry through the ziplock brand freezer bag no problem, but when we placed those in the opsak no odor until we broke then seal, but wow was it concentrated in the opsak. I have been very pleased with these bags so far. I would say they are a bit on the pricey side, but so much more compact than a bear canister for areas where I'm more concerned about rodents then I am bears.

I got about 200 rugged backpacking miles on this Loksak before I developed a small pinhole and had to replace it. I used it on the Appalachian Trail where, in conjunction with a Ursack, I tied it to the base of a tree (well away from my campsite) every night. No animal ever found my food! On the occasions where bear cables were provided, people's food bags were chewed through by mice that climbed the cables. No mouse ever discovered my food. I can't say enough good things about this Loksak. I didn't have any problems with the zip closure and it never popped open on me, even when crammed in an over-stuffed backpack. I would definitely buy this again because the peace of mind in the backcountry is worth it.

We live in Alaska and nearly all of our hikes are in bear country. I used one on the Resurrection trail on a 6 day hike to hold my snacks together and was pleased with it despite the expense. I was then convinced to use the other two for my boys (8 & 11 years) to carry their snacks for the Chilkoot trail during a 5 day hike. It helped keep their snacks and wrappers together with an added assurance that food scents were kept to a minimum. Since we do a lot of hiking in bear country I am concerned about them carrying food in their packs and attracting unwanted bear attention, but like for them to have some on hand in case they get lost or separated. The adults carry the rest of the food and garbage in our family. I liked their flexibility and that they could fit easily into the pocket of our packs. I felt pretty secure about their effectiveness although the boys were rougher with the bags and the top of one tore, but it still could be sealed. I should have explained their use and expense beforehand, because they took better care of them after I did. I didn't trust the effectiveness enough to allow the boys to carry the fragrant pepperoni, though. Nor am I sure how effective they are if small punctures are made with regular wear and tear. Be careful nothing sharp or angular is kept in the bags and you'll get more use out of them.

Yes, these are a bit tough to get closed, but with patience they work great. They are durable, but need some TLC. None of the these are reasons I would not use them. They give that extra level of security when hanging our food that smells won't get out. We used 3 of them for 10 days on the Colorado Trail and opened and closed them 5 or 6 times a day and never had a problem. We'll use them again this year.

There are seams connecting the bag to the zipping mechanism. At this point the bag fails when a slight tug pulls the seam apart. Very fragile bag for the use. Better off buying the ziplocs and double bag if necessary.