38 Songs Wireless Doorbell Remote Control 100m w/ Light DIY designing, you don't need to seek help from professionals or set line or excavate a hole on the wall. You can install it anywhere you like in your apartment. 38 sound types to choose from 'Up' & 'Down' switch, including many popular songs. 3 levels volume control. Working distance: approx. 50 meters or 164 feet . Powered by: Remote 1 12V 23A battery (MN21/MS21 V23GAL L1028), Chime 110V .