Homecube Portable Doorbells Wireless 58 Chime / Over 1640 Ft Range / 2 Push Button Wireless Doorbell with 2 Plug-in Receivers 4 Volume Levels with LED Indicator (2 Push Button with 2 Receivers) TRANSIMISSION RANGE: Wireless doorbell operating range of over 1640 feet ( in open area), you can receive the signal whether you are busy working on your computer in the home office or sharpening your culinary skills in the kitchen. FEATURES: 52 different ring tones,4 levels of adjustable sound volume give you complete control over the sound of your door chime with LED indicator. The transparent compartment at the bottom of the transmitter allows visitors to leave message for you. SIGNAL ALERT: A paging device for the elderly,can signal for care when they need it the most. it can allow immobile or bedridden patients to conveniently page to contact their loved ones or care takers. BATTERY: No batteries required for the receiver. Simply plug it into a power supply (120V US Standard), Transmitter comes with 12V 23A ALK battery for the push button remote is INCLUDED. EASY INSTALLATION: One door chime can be plugged into an electrical outlet in your home, And the push button can be fixed to the doorframe with the screws provided, or attached to the wall using double-sided adhesive tapes.