This Byron DBY-23521 Wireless Doorbell comes with a portable chime unit, giving you the flexibility to move your door chime throughout your home, garden or garage. The portable unit requires 3 x AA batteries (not included), and will ring up to 175 metres (open distance) from the bell push.Easy to install, with no wiring required.Choice of 8 high quality melodies, multi coloured visual alert, adjustable volume & compatible with all other Byron "DBY" products.Wire free.Weatherproof.8 melodies.Volume control.Operating distance 175m.Fixings included.Batteries required: 3 x AA (not included) and 1 x CR2032 (included).EAN: 8711658441900.