iMeshbeanWaterproof Rechargeable LCD Shock Control Pet Dog Training Collar with 100 Level of Vibration + 100 Level of Static Shock Rechargeable and Waterproof LCD digital remote control electric training collar remote control electric shock devices Convenience of easy-to-read LCD screen shows the stimulation level. Over 3,000 different identity codes to prevent conflicts with other e-collars. 4 modes: static shock/ vibration/ beep/ light with 100 levels of vibration & static Rechargeable Handset + Rechargeable Collar Receiver. No More Replacement Batteries Required! NOTE: Piece in Collar is made to rattle by design, it lets the collar know if the dog is in movement so it can come out of sleep mode, and if the dog is not moving to go into sleep mode to save battery life.