TEQIN Obell 1+2 Batteryless Wireless Self-powered Doorbell Ring Waterproof Door Chime with 38 Ringtones Adjustable Volume, No Need Battery for 1 Transmitter and 2 Receivers 3in1 Kit(Ivory White) Innovative design: TEQIN Obell Wireless Self-powered Doorbell with 1 Remote Button Transmitter and 2 Plug-in Receivers,Operating at over 100 meters Range With 38 default tunes and 4 levels of adjustable volume,adopts Creative Technology to achieve the Smart Home Life of Batteryless, Self-powered generator system. This doorbell is intended to make more convenient for user, better for environment. Best Collocation: 1 remote button transmitter(installed on the front door) is equipped with 2 plug-in receivers(one for downstairs living room,another for upstairs bedrooms).This collocation will be very intelligent and powerful for your life even you are away from the front door or trapped with housework. With wireless doorbells, signal can pass through doors, walls, floors. Remote distance can be up to 100m outdoor, 30m indoor. Multi-function strength: This doorbell is not only can be used as its own attribution(door ring),but also a stronger alert device and contact/paging one. Installed in the apartments or office buildings to make your work and life more efficient. Meanwhile,fixed transmitter on the bedside of patients/elderly/children, receiver in carer's room.It allows immobile or bedridden patients to conveniently page or contact their loved ones or care takers. Intelligent coding/decoding: The coding of bell is done when out of factory, users can use it directly with exclusive coding. Only when it needs to be added or replaced the transmitter or receivers, coding is essential. By coding, one transmitter can control several receivers while multiple transmitters can govern one receiver easily.Please follow up attached manual to make settings. Reliable quality: LED indicators on both transmitter and receiver can conveniently tell you not miss someone at the door.Transmitter service life is up to 200000 times pressing.38 selectable ringtones is good for your ears and keep good mood, the volume is high enough to cover your house.Package includes: 1 x Doorbell Transmitter with 3M adhesive tape (button); 2 x Doorbell Receiver; 1 x Backup 3M adhesive tape.