Self Powered IP68 38 Chime Wireless Home Security Electric Doorbell(Model B ) Features: Ringing flashing design, can provide much convenience for hearing impaired people. With strong signal and far transmission function. Up to 100 meters wireless range in open area, reduces the influence of distance successfully. Waterproof and moisture proof design, can be installed anywhere and anytime, not considering the bad weather. Press to generate electricity without battery, energy saving and practical in use. Specifications: Color: Black Optional Model: Model A(3Transmitter&amp;3Receiver), model B(2Transmitter&amp;3Receiver)(optional) Transmitter&nbsp;Size: Approx.45x70mm/1.8x2.8in Receiver&nbsp;Size:&nbsp;Approx.50x67mm/2x2.6in Model: Wireless electric doorbell Material: ABS plastic Wireless Distance: Freely accessible 100 meters without interference in open area Ringtone: 38 chord music Volume Adjustment: 4 levels controllable, ringing flashing Wireless Frequency: 433.92MHZ Use Environment: -10-+55 °C Waterproof Rating: IP68 Package List: 3 x Transmitter<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> 3 x Receiver<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> 3 x Double-Sided Sticker<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> 1 x User Manual<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> (For Model A Only)<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> or<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> 2 x Transmitter<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> 3 x Receiver<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> 2 x Double-Sided Sticker<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> 1 x User Manual<br style="font-size:14px;white-space:pre-wrap;box-sizing:border-box;-webkit-tap-highlight-color:rgba(0, 0, 0, 0);color:#191F25;font-family:&quot;font-variant-numeric:normal;font-variant-east-asian:normal;line-height:21px;widows:1;" /> (For Model B Only)