This Byron BY535 Wireless Doorbell Kit comes with both a plug in and a portable chime unit (which requires 3 x AA batteries, not included). Both units will ring up to 125 metres (open distance) from the bell push. With additional flashing light function these chimes are ideal for the hearing impaired or for a noisier environment. The Byron BY535 is the perfect, easy to install doorbell kit for any home, no need for wiring. Just follow the simple step by step instructions and your new doorbell will be working in no time. Included: 1 x Bell push 1 x Plug in door chime 1 x Portable door chime 2 x Black and 2x Grey Cover. Easy to install, with no wiring required Weatherproof bell push LED flashing lights assist when hearing impaired or in noisy rooms Choice of 6 melodies Adjustable volume control Clear audible sound from the high quality speaker. Wire free. Weatherproof. 6 melodies. Volume control. Operating distance 125m. Fixings included. Batteries required: 1 x button cell (included) and 3 x AA (not included).