Long range and stronger signalWorks within 300 meters in open space, the signal of this doorbell penetrates obstacles very well. You can connect the receiver anywhere you want in your home. No wireless interference issues. Super Easy SetupThe receiver requires no assembly or batteries, just plug it into an electrical outlet. The transmitter can be attached to the front door with the included screws or stuck to the door with the included adhesive. Excellent quality and waterproof IP44This doorbell is made of ABS material, non-toxic and safe. The transmitter is IP44 waterproof and acceptable for outdoor use. Protects against dust, rain and high temperatures. No electromagnetic radiation. CE certified. Energy saving and long lifespanLow power consumption, energy saving and durable use. The transmitter battery can be used for more than 15 months. The transmitter can support more than 100,000 times clicking. LED IndicatorThe doorbell (transmitter) and receivers have LED indicators, if someone presses the doorbell, all devices will flash in blue light. 36 melodies available, 5 volume levels adjustable from 0 dB to 85 dB. Features: Wide application Satisfies all types of home decoration, official buildings, hotels, factories, commercial activities. Emergency contact for the elderly, pregnant women, patients, etc. Energy saving< /p> Low consumption, energy saving and environmental protection, maximum power is 2W, standby consumption is 0.5W. How to install the doorbell: You can attach the doorbell (transmitter) to the wall or door frame with the adhesive tapes or you can attach it to a surface with the included screws. Plug the receivers into n Any electrical outlet you like and you can use the doorbell. Technical specifications: Transmission range: 280 meters (unobstructed) Ringtones : 36 different ringtones Volume: 5 levels adjustable (0 dB ~ 85 dB) Power supply (receiver): AC 110-240V 50/60 Hz Power supply (transmitter): 1 12V 23A battery (included) Waterproof (transmitter): IP44 Scope of delivery: 2 x Button (transmitter) 1 x Receiver 4 x Screws 2 x 12V 23A battery for transmitter 1 x Screwdriver 2 x Adhesive Tuban 1 x Instructions for use