Convenient Wireless Design: No need to bury wires, saving time and effort. The transmitter can be adjusted to 8 intensities so you can find the right level for your dog 4 Adjustable Distance Levels: There are 4 adjustable coverage levels. The radius from the center of the transmitter is 50m, 100m, 150m, 200m. Your dog can play freely and safely without worrying about being restricted or getting lost. ADJUSTABLE COLLAR & IP68 WATERPROOF RECEIVER: The leash is adjustable from 8 to 25 inches, suitable for all types of dogs weighing between 10 and 120 pounds. The receiver is IP68 waterproof, allowing your dog to swim, shower and play in the rain. Rechargeable collar: The transmitter and receiver have built-in rechargeable batteries, which do not need to be replaced frequently, are easy to use and have a long service life. Support multiple receivers: These devices support multiple collars, so you can purchase additional collars and add them to the system.