I have swam in my 177h with no problems, infact i have done a drop test from a 5m board to the bottom of a 5m pool with no probs, i wore it last week while sailing/capsizing laser picos, i use that or a noob cased sterile sub or my sfso and my ingy if i am going to get wet, infact the only rep i have not swam in is my porto chrono and speedy, i remember going in a pool with my fiddy before i remembered i was wearing it, but be aware i have checked the seals crown and case backs on them all, Panerais all get a bit of work on the CG and lever so that it sits tight on the crown.