I have been using the Orvis Double sided waterproof Small fly box for a year now with great results. It fits great in my Chinook pfd pockets. Other than a few drops getting on it, it has stayed clear of submersion. Well on a recent river trip, I found myself submerged quite a few times during that trip. I didn't get a chance to break out the fly rod, so I never opened up my fly boxes. After getting home and having lost nearly everything to the river, I hung my PFD in the closet and left it. Fast forward 2 weeks to yesterday. Bro in law wants to fly fish. Get my rod fixed up and go get my fly boxes from my pfd. I opened it up and immediately got hit in the face with a nasty smell. Both sides were wet inside! Wow. It wasn't waterproof enough to keep the water out, but waterproof enough to keep the water in. The other fly box I had in the other pocket was fine, but this one turned sour bad. The dye's in some of the materials were coming off on my fingers as I moved them around. I tried to salvage what I could of the flies, and left it to dry under a fan. I've never had this happen to any of my boxes before. So now I can add a fly box to my list of things lost. I think it may have been the river's last..."screw you and the fly box you rode in with." :(
It was preceded in death by a brand new TFO 10wt rod, Pflueger Trion 1990, new backing, new line, new leader, and a separate box of freshly tied poppers.
I promised myself I...wouldn't....cry....
A buddy wrote part 1 of the trip here. He's a great storyteller.