Material: plastic Color: black Waterproof quality: IP55 Working temperature: -30°C to +70°C Working distance: 300 m (without barrier) Operating 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 dimensions (L x W x H): 6 x 6 x 1.5 cm Transmitter dimensions (D x H): 7.8 x 5 cm Package 1 includes: 1 receiver, 1 transmitter Package 2 includes: 1 receiver, 2 transmitters Easy to Trigger - The dog bells activate with a gentle nudge or slide across the touchpad using nose or paw. The interval between two chimes is approximately 20 seconds. No pressing required. Suitable for small and large dogs. Easy to Install - All dog doorbells are wireless. Use included 3M double-sided tape to mount the transmitter on doors, floors, or walls. Simply plug the receiver into a standard electrical outlet. Installation is quick and convenient. Adjustable Sound and Volume - Offers 55 selectable ringtones and 5 volume levels ranging from 0 dB to 110 dB. Can be set to 0 dB (mute) when silence is preferred. 300m Wireless Range - Includes transmitter and receiver with easy pairing. Provides stable signal transmission and strong interference resistance. IP55 Waterproof - Built-in waterproof sealing ring protects internal components from dust and water, ensuring reliable performance in rainy conditions and extending product lifespan.