The Scuba Rattle Stick is a fantastic tool. For those that don't know what a Scuba Rattle Stick is, it is a short stick made of a corrosive-resistant metal, with a clip at one-end which a lanyard can be attached, and a rattle on the other end. The XS Scuba Rattle Stick with Clip can be used as a signal device, by shaking it to get your buddies attention. The sound it makes is nice and loud underwater for easy identification of the noise source. Need to run silent, XS Scuba's Rattle Stick has a cap with magnetic to prevent unwanted sounds.