[Upgraded Rechargeable Version] WOLFWILL Waterproof Wireless Fencing System 500 M Radius Remote Control for 2 Dogs w/ 2 Receiver & LED Display Transmitter-Black Transmitter is equipped with digital display device, which shows current signal intensity directly (0-100 levels). TWO modes are available: ELECTRIC SHOCK and SOUND CONTROL, with a range of up-to 5000 square meters. If your dog runs out from designated place, its receiver will initiate training function automatically. Firstly, your dog will be warmed by SOUND, then it will be shocked by STATIC ELECTRICITY to go back to the safe place. WOLFWILL dog wireless fencing system with Completely Wireless System & Super Large Controllable Range:take the transmitter as center, it's biggest remote-control semidiameter is 500 meters. The signal intensity of transmitter can be adjusted from 0 to 100 levels, and the correspondent distance of receiver should be 20-500 meters. TWO rechargeable waterproof receivers with soft durable straps allow you to train two dogs at the same time..Step 1: short press the power switch to turn on the transmitter, and then long press it for entering into the pairing state. Youll see the 1 dp on the screen and it only lasts for 10 secs. (PS: need to turn into pairing state again if not pairing in 10 secs.) Step 2: short press the power switch to turn on the receiver and then long press for pairing with the transmitter. The pairing is done when you hear a clear long sound Bee.Need to pair them in 15 seconds or you need to restart to pair them.