Specifications: Range 100 meters wireless door bell, free range without obstruction. 32 melodies to choose from. Can be changed from a touch of a button. Waterproof remote button light up when pressed. Remote button has double sided adhesive on the back of it. Built in double speakers, makes the bell sound more clear. Ideal for house, office & garage, etc. Easy to install and remove. Instructions: 1. Press the small gap on the underside of the remote control with a flat screwdriver. 2. Open the remote and insert the 12V battery (small battery, included). 3. Close the remote again and then stick it where you want with the adhesive back. 4. Insert the 2 x AA batteries (not included) into the receiver. Please check polarity spring side is Negative side and plate side is positive side. Always use good quality batteries for best result. You can buy from listing. 5. Use the button on the side of the receiver to change the melody to your favourite. Item Name: Wireless Doorbell Material: Plastic Transmitter Battery: 12V Battery (Included) Receiver Battery: 2 x AA Batteries (Not Included) Features: Easy Installation, 32 Chime, 100m Supported, Home Security Length: 10cm/3.94" (Approx.) Width: 9cm/3.54" (Approx.) Height: 3cm/1.18" (Approx.) Notes: 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. Package Includes: 1 x Remote Control Button (Transmitter, with Battery) 1 x Wireless Musical Doorbell (Receiver, No Batteries)