the revolutionary r.a.p.t. series training collars offer a versatile design for any situation. features a curved transmitter with a strap for multiple grip positions and a rapid access button for quick corrections. the system can expand to control 2 or 3 dogs. the newly designed collar unit is small, lightweight, fits in the palm of your hand, and is waterproof and rechargeable. fits small to large dogs. the transmitter floats on water, and both collar and transmitter come in waterfowl camo.