If you are looking for a watch to wake you via vibration from deep sleep, look no further. I wear the watch so that its entire bottom surface is flush against the inside of my wrist. The watch vibration will be in contact with the bed creating a louder vibration sound. I can't hear the high pitch of a normal watch alarm but the low frequency produced by the vibration as well as the physical vibration itself is easily enough to wake me on first try. The vibration consists of three pulses for 10 seconds and I back it up with two more alarms for snooze, each separated by one minute. Thanks Casio!