CACAZI FA78 Self-Generating Wireless Doorbell for Home Transmitter + Receiver Smart Doorbell - White/EU Plug ?Self-generating transmitter: No battery is needed. A finger press can trigger the generator to convert into electrical energy ?Not just a doorbell but also a pager: The elderly,children,and pregnant women have needs,just click to know,sleep at night with peace of mind ?Easily deal with various places: In villas/apartments/office buildings/hotels/nursing homes and other places ?5 levels of adjustable volume whatever you want: The doorbell has five levels of volume,which can be adjusted freely. (Volume can be adjusted,light reminder) ?Anti-interference,no crosstalk: Digital circuit design,multiple sets of use will not cause cross talk,effectively avoiding the troubles caused by mutual interference between neighbors ?Specifications: ?Model: FA78 ?Music: 60 music tracks ?Volume: 5 levels of volume (adjustable to flashing light only) ?Transmitter: No batteries required,press to generate power ?Receiver: Light only when the bell rings ?Transmitter size: 74 x 40 x 20.3mm ?Receiver voltage: plug-in power use (AC110V/220V) ?Receiver size: 84 x 52 x 29mm ?Remote control distance: 150M in a straight line on open ground Package included: ?1 x Receiver ?1 x Transmitter ?1 x English Instruction Manual ?1 x Installation Kit ?Other items not included