Description: 1.The doorbell can use in office,home, hospital,factory,restaurant or any where you need it. 2.The receiver unit can be free standing or wall mounted using the included hardware. 3.Install the push button with provided double sided tape or screw it to the wall (screws are included). 4.300 meter receiving distance (In the open area),Stable quality is ideal for villas, hotels, schools and other areas. 5.The button cannot be placed on an iron door because it will interfere with the signal. Specification: Brand: CACAZI Model:A10 Weight: 50g Color: Black/White Volume:3 levels Ringtones:38 pcs Transmitter size:75 x 51 x 20mm Receiver size:95 x 65 x 24mm Transmitter battery type: 12 V 23A alkaline battery (battery not included) Receiver battery type: 3 x AA batteries (battery not included) Waterproof grade: IP44 Package Included: 1 x Doorbell transmitter 1 x Doorbell receiver Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.