I have used one for about 5 years and it is the automatic/manual type. Mine will only inflate automatically if submerged in water. I have worn it in damp conditions and rain before and it has never deployed. I check the window to see if the green or red is showing. If red you must re arm it which is about 29 dollars. It turned red about a year ago and I went ahead and re armed it and keep and extra re arm kit in the boat just in case because we do fish out of town sometimes. I now have one for my wife who is my tournament partner and we love them because they are so comfortable. We purchased ours at BPS during the spring when they put stuff like that on sale. Make sure when buying that you get one that says it has 35 lbs.of buoyancy.