Color: White
wireless doorbell chimes systems are expandable and can be pared with over one receiver and transmitter including accessories such as door and motion sensor; one doorbell receiver can work with 20 transmitters and each receiver can be set with different sound for different entry gate.
Features:
1). 52 Selectable Ring Tongs; 4-level adjustable volume; 25~85 dB
2). Super Long Operation Distance Range: 500 feet at open area.
3). Easy To Install:  Easily to add additional transmitters or receivers and other sensors
4). Low Power Consumption: Lower power red LED Indication; alkaline battery used, one year battery life consumption.
5). IPX3 Waterproof protection plastic case optional.
**Attention**Working distance will be effected by real conditions. If there are several metal doors, concrete wall, concrete floor, it will impact the emitting distance hugely.
For examples, If you put the receiver at second floor, \"Push Button\" is installed at the gate, there is a concrete floor directly between them. The emitter distance is maybe around only 50 meters.
If you meet any problems, pleases try it at the open area then check the real surroundings and contact us.
Specifications:
Maximum 500ft /150m operating range in open area.52 unique ring tones4 volume levelsFlash LED indicatorsReceiver 
Battery: 23A 12V Alkaline
Transmitter power consumption: <10mW
Volume range: 25 to 85dB
Working Frequency: 433.92Mhz
Wireless Coding Method: Benavis
Operating Temperature: 5°F to 140°F or-15°C to 60°C;
Dimension: Receiver: 82x82x45mm/
Push Button: 82x40x14mm
Package List:
1*Push Button/1*receiver/2*screws&Anchors/ 1*double-sided adhesive tape/1*user manual/1*12V 23A Alkaline battery(Installed)