Learning code matching of chime and transmitter to avoid interference
Wireless working range in 150 meters in open area
38 pcs euphonic melodies in chime
Select the interesting melodies on chime freely
Sound volume can be adjusted in 4 level from quiet to 85dB
Three working method of chime: only melody or only lighting or melody+lighting
One chime can match with 16 transmitters ,no limition for one transmitter match with how many chimes.
Transmitter with self-name card and IP55 proof for outdoor using.
Frequency in 433MHz 
Power of chime 3pcs AA size battery
Power of transmitter 1pcs CR2032 battery