The akko star wireless digital electronic bell is a convenient bell for you. It has an LEDnightlight with flash. It is powered by a battery. It has 32 high quality sounds. It has a self-learning function which avoids interference. It operates at a 100m range in open air. It has 4 level volume control, up to 95dB. The bell push is waterproof IP44. The receiver has 3* AA1.5V batteries.