Features: 1.2 Receivers: One doorbell with two receivers, you can place the receivers in different rooms or floors, never missing every visitor ringtone. 2.Self Generating: The wireless doorbell is self generating, no need wiring, no need battery, has long transmission distance. 3.Multi Purpose: The doorbell can also be a pager, for babies sleeping alone, the elderly and pregnant women, just click when have needs. 4.Strong Signal Reception: The device can be used wirelessly through wall, with strong penetration, one to one signal pairing, no worry about stringing with others. 5.IP68 Grade: Doorbell transmitter has IP68 protection grade, waterproof and not afraid of the sun, featuring long service life. Specification: Item Type: Wireless Doorbell Set_x000D_ Material: ABS_x000D_ Use: Can be used in home, villa, hotel, factory, for the elderly, patient, pregnant women call with one key_x000D_ Doorbell Transmitter:_x000D_ Power Source: Self generated_x000D_ Doorbell Receiver:_x000D_ Power Supply: AC 100-230V_x000D_ Power Consumption: 0.25W_x000D_ Ringtone: 38 ringtones_x000D_ Transmission Distance: Open space >150m_x000D_ RF Frequency: 433MHz_x000D_ Ringtone Volume: 50dB per meter PackageList: 1 x Doorbell 2 x Receiver 1 x Sticker 1 x Manual Note: 1. Do not place the product in an environment that is too corrosive, humid and high temperature._x000D_ 2. Please supply power according to the voltage used. Using other voltages may cause fire and product damage.