Numerous times I've taken the OtterBox 1921 out on the Missouri River on a 2005 Yamaha WaveRunner GP1300R and my phone has lived every time. Doing over 70MPH on the water while jumping barge wakes is not the ideal place to have a phone, but with the OtterBox 1921 protecting my phone I don't have to worry. The Treo goes in the storage compartment and is then out on the shore or sandbar being used seconds later when taking a break and hanging out with friends...