Product Description Material: Plastic Color: Black Waterproof Rating: IP55 Operating Temperature: -30°C to +70°C Range: 300 m (without obstacles) Frequency: 433.92 MHz Volume: 0-110 dB (5 levels adjustable, with mute function) Transmitter Battery: 12V 23A alkaline zinc-manganese battery (built-in) Receiver (length x width x thickness): 6*6*15 cm Transmitter (diameter x thickness): 78*5 cm Package 1 includes: 1*receiver, 1*transmitter Package 2 includes: 2*receivers, 1*transmitter Easy to Trigger: These dog bells only require a light press or slide of the paw on the touchpad to activate the wireless doorbell. The interval between two rings is approximately 20 seconds. No need to push hard – suitable for all dogs, small or large. Easy Installation: All dog doorbells for potty training are wireless. Attach the transmitter to the door/floor/wall with 3M double-sided tape, or even a board, and place it wherever you need it. Simply plug the receiver into an electrical outlet. The setup is simple and easy to use. Adjustable Sound and Volume: This smart dog doorbell offers 55 ringtones and 5 volume levels, ranging from 0 dB to 110 dB. Set it to 0 dB (mute) when needed. 300m Wireless Range: The pet doorbell comes with a transmitter and receiver. The transmitter and receiver can be easily paired. Stable signal transmission and excellent anti-interference performance. IP55 Waterproof: The built-in waterproof sealing ring protects the internal components from water and dust, extending its lifespan. It can function normally on rainy days.