Fosmon WaveLink 51004HOM Wireless Door Open Chime (120M/400FT | 52 Tunes | 4 Volume Levels | LED Indicators) - 1 Magnetic Door Entry Alert Security Contact Sensor, 1 Wireless Doorbell Plugin Receiver [MONITOR THE AREAS MOST IMPORTANT TO YOU WITH WAVELINK WIRELESS DOOR CHIME] WaveLink wireless door chime offers a generous detection area of nearly 400 feet. Far enough to cover every window and door in your house. Expand the system by pairing up to 10 wireless doorbell receivers to one magnetic door entry alert security sensor, or 10 door contact sensors to one receiver. The choice is yours. [52 UNIQUE CHIMES] 52 unique ringtones and chimes allow your wireless door and window entry alert system to meet any need. Add more receiver or sensor to setup different chimes in multiple areas for front door, back door, sliding door, main floor, basement, garage, toddler room, baby room, play room, pool door, shed, storage, attic, gates, office, warehouse, back of shop, apartment, mobile home, RV, dorm room, and many more possibilities. [PROVIDE PEACE OF MIND FOR THE HEARING IMPAIRED] With the built-in LED indicator, the wireless door alert receiver and sensor offer additional assistance when coupled with the receiver to the hearing impaired. Difficulty hearing is no problem with WaveLink wireless system. [EASY INSTALLATION] With its simple wireless plug-in and double-sided tape, the wireless door and window chime sets up in seconds. It gives you the opportunity to spend your time elsewhere. All hardware is included, and ready to use. [LIMITED LIFETIME WARRANTY] The Fosmon WaveLink wireless door chime and its components come with a limited lifetime warranty Receiver Voltage: 110V AC Battery: 1.5V AA Alkaline Battery Power consumption: &lt;10mW Volume: 25-110dB Range: 400ft (120m in an open area) Frequency: 315/433 MHz  2MHz Operating Temp: 5F-140F (-15C-60C) Receiver Size: 3.17x3.19x1.12in (80.5x81x28.5mm) Transmitter Size: 2.95x1.97x0.63in (75x50x18mm) Receiver Weight: 3.03oz (86g) Transmitter weight: 0.92oz (26g) 1x Receiver 1x Transmitter 1x User Manual Mounting hardware