A stylish portable battery operated wireless doorbell with visual indication and 38 melodies. Easy to setup and use, the internal chime unit can be wall mounted or free-standing. When activated a green LED flashes on the internal unit making it ideal for noisy environments or the hard of hearing.Battery : receiver[tab]4.5Vdc (2 x AA)[br]Battery : transmitter[tab]12Vdc (23A)[br]Transmission frequency[tab]433.92MHz (±150kHz)[br]Transmission distance[tab]Up to 100m (clear line of sight)[br]Dimensions : receiver[tab]110 x 30 x 75mm[br]Dimensions : transmitter[tab]80 x 20 x 36.5mm[br]Weight : receiver[tab]86g (without batteries)[br]Weight : transmitter[tab]24g (without battery)