Modern and stylish exterior design, Satisfy all kinds of home furnishing, office buildings, hotels, hospital,factories etc. There are 45 different polyphony melodies to choose from the doorbells,so you can enjoy different chime every day! 4 Adjustable volume from 0 to 100dB,this option is great for nap time! LED Flash,When the button is pressed, the doorbell transmitter and receiver flash at the same time with obvious brightness .LONG DISTANCE WIRELESS RANGE:The wireless signals up to 1000 feets in opening space and doesn't interfere with other equipments in your home or those of your neighbors;ensure that you will never miss any visitors,even if you are several rooms away.WATERPROOF AND ENERGY SAVING TRANSMITTER: low power consumption with packaged 12V alkaline battery,IP44 waterproof remote control push button tested in temperatures of -4°F to 140°F;withstand the harshest weather.EASY INSTALLATION:Simply plug the receiver into a power outlet and attch the transmitter on the wall or door frame with adhesive patch or screws included.How to Installation: ● 1.Choose the installation location, wipe clean. ● 2.Method 1: Remove the bottom cover of the transmitter and double-sided adhesive sticker. Place it in the place where it needs to be installed. Press hard for 5 seconds until it is secured.Method 2: There are reserved screw holes on the back of the transmitter back case Attach the back case to the wall with screw spikes. Package Contents：1 x Transmitter (battery included) 1/2 x Plug-in receivers （AS YOUR CHOOSE) 1 x Adhesive patch 2 x Screws 1 x Key 1 x User ManualPress the button, super learning code can freely learn to match, can be unlimited matching receiver and button.The transmitter without screw chuck design to achieve waterproof and dustproof.