Karl: usually a hefty dry bag; not the ones that look like heavy duty ziplock bags - I'm talking about the roll the top down and clasp bag - plus IPX7 or 8 waterproof rating is a good combination.

However, In my case - electronics die from just plain abuse while on the boat. We're not gentle on the stuff and I can't tell you how many foretrex flew off my wrist (not because of the pin - but because the damn thing slid down my wrist). This past Tybee we managed to lose a foretrex and then during the last leg (disaster) launch, I landed on top of the GPSMAP76 and cracked the screen when we launched off a wave.