Import Notes: In order to get the best performance of this Wireless Dog fence system, Please install the transmitter On the wall higher than 3.5 ft. How does it work Turn on the transmitter, and it would emit a 433Hz radio signal around your house. Your pet wears a lightweight receiver collar that keeps connecting with signals from the transmitter. Your dog could enjoy his time freely in the signal-covered area, and when he tries to walk close to the edge of the signal-covered area, the receiver would deliver a series of corrections to force him to get back. Correction system Pre-correction warning tone: when the dog reaches the edge of the signal field it will hear a warning tone that lasts about two seconds. If the dog does not return to the safe area it will receive a continuous correction by warning tone static shock until it returns to the safe area.Run-through prevention: the receiver automatically increases the correction as the dog enters the signal field. The dog cannot “run through” the signal field without receiving strong correctionSet up collar receiver Before first using our Rechargeable and Waterproof Collar Receiver please make sure to charge it at least 4 hours. Turning on the power button on the receiver and the red LED light will turn on. When the indicator light turns flashing red it means the battery is running down and needs to be recharged. FOCUSER Electric Wireless Dog Fence System, Pet Containment System for Dogs a... FOCUSER Electric Wireless Dog Fence System, Pet Containment System for 2 Dogs... Add-on Collar Receiver Only Extra Collar Belt Add-on Transmitte For Expansion Add to Cart Add to Cart Buying Options Buying Options Add to Cart Suitable 1 Dog 2 Dogs Collar Receiver Only Belt Only Transmitter Only Waterprrof ✓ ✓ ✓ ✓ no data Adjstable Shock Level 1 - 4 1 - 4 1 - 4 no data no data Expandable ✓ ✓ no data no data ✓