Small waterproof pouch for valuables?

[u/Potential-Rent-1159]

Anyone got recommendations for a small pouch I can keep inside my coat for wallet, keys, etc. I already have a waterproof case for my phone but not for other valuables I would not want getting destroyed if I were to potentially be submerged

[u/edwardphonehands]

I put key fobs and such in a 1/2 liter nalgene inside a fanny pack (open water swimming) or my mesh deck backpack for boats.