CACAZI FA78 Smart Wireless Doorbells Set with Transmitter/2 Receiver Self-Generating Home Doorbell - Black/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: •2 x Receiver •1 x Transmitter •1 x English Instruction Manual •1 x Installation Kit •Other items not included