- OPSAK Odor Proof Dry Bags for Backpacking

The OPSAK is a 20-liter barrier bag whose film cuts the food smells that get rodents and bears interested in your pack, closed by a press-to-seal waterproof zip. Used inside an Ursack, inside a canister, or in a hang, it is the cheapest way to reduce your scent signature, and at 34 grams it costs nothing to carry. Two honest limits. First, it is not bear-resistant and does not satisfy regulations that require an approved hard canister, so carrying it where a canister is mandated risks a citation and a food-conditioned bear. Second, it is a consumable, not equipment. The seal channel and the film degrade with repeated opening, folding, and contact with sharp food packaging, and a bag opened several times a day often stops sealing reliably within a few weeks. Once the closure is compromised the odor barrier is gone. Even at its low price, budget for replacements.