do you have the watch with instructions? I found out a long time ago just because a watch has a 200m or a 300m WR rating it doesn't mean that the manufacturer will warrant it for use in scuba diving activities. if the paperwork say's it's rated for scuba, go for it.. if not you may not want to chance it in case something leaks. I usually look for a minimum of 200m Diver's ISO watch rated for scuba diving and have never had a failure. just make sure the crown is snugly screwed down if it's rated and enjoy.