I carry a spare set of sunglasses. It sounds like I carry the exact same "film canister" type that OM carries. I have backups for fire (matches, lighter, fero rod). Sometimes I carry an empty extra water container. I also carry prescription glasses to backup my contacts. I carry three cutting instruments (Mora, multitool, EMS shears). I carry an extra strap for my hammock tree huggers, and a little extra line for the suspension. This is in case the trees are a little wider or farther apart than expected, or if something breaks. I carry extra tie-out line for my tarp or for something unexpected. I guess my needle and thread is extra. I always carry chlorine dioxide tablets, are those extra?
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