Famili Dog Trainning Collar Transmitter for DTC1(Accessory Only, Can Not Be Used Alone) Accessory Only, Can NOT Be Used Alone Advanced RF 434Mhz Technology boosts range up to 330 yards. Built-in high capacity lithium rechargeable batteries (500 mAh for transmitter). Convenient, easy-to-read Backlight LCD screen that shows the stimulation level. 4 modes: static shock, vibration, beep and light.