Do you carry a can opener on the AT? I'm guessing that with gas station mini marts as resupply points, there often won't be foil packs of tuna. So a can of tuna for the first meal back on the Trail is probably better than going low on protein. A P-38 type can opener is only 8 grams; the weight penalty is mostly in the liquid in the can, then the can itself, and the can opener is the least part.

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