This wireless doorbell by SURFOU is the perfect addition to any home. With an ultra-long 1300 feet wireless coverage, you'll never miss a visitor again. The doorbell is waterproof and operates on both AC and battery power. It comes with two plug-in receivers, two push buttons, one door sign, and 2 12V batteries, making it easy to install right out of the box. The doorbell features special functions such as 0 mute, memory function, and expandability, and has a sound level of 110 dB. It can be installed with either adhesive or screws and has LED lights for easy use in dark environments. This doorbell is not only great for alerting you of visitors but can also be used as a music alarm clock for children or a pager for the elderly.