Ever missed a knock on the door because you were doing the dishes listening to music or in the shower now your visitors wont be left standing in the cold thanks to this melodic doorbell features 32 melodies ringing tones optical call signal integrated loop for hanging up receiver requires 3 x 15 v aa not supplied maximum 65 db volume an external power supply 45 v can be attached cableless doorbell in 433 mhz technology weatherproof ip44 function led can be mounted u