Nexa MLR-1922/SET Wireless doorbell, battery powered complete with push buttonSet with doorbell and push button. In addition to functioning as a normal doorbell with a push button, the doorbell can also receive signals from a motion detector and magnetic contact or remote control if desired. There are 6 selectable tones so different transmitters can give different ringtones. The sound level can be set in 4 differentlevels; High – Middle – Low – Mute.- Battery operated- 32 memory slots- Easy installation- 6 selectable ringtones- 4 sound levels - Up to 150 meters range- Wall bracket includedSpecifications Power source doorbell: Battery: 3 x AA (not included)Power source push button : Battery: 1 x CR2032 (included)Protocol: System Nexa (433.92 MHz)Range: Up to 150 mIP classification: Push button IP44, receiver Indoor useDimensions door bell (W x H x D): 65 x 108 x 68 mmDimensions push button (W x H x D): 30 x 70 x 15.5 mmProduct document< /p>