Features:

55 Bell Chimes Available: user can choose the tone as he like.

Simple Operation: comes with 1 transmitter and 1 receiver, easy to pair the transmitter and receiver.

Memory Function: the chime user set before won't change even the power is cut off.

300M Wireless working Distance: Stable signal transmission and good anti-interference performance.

IP55 Waterproof: built-in waterproof sealing ring can protect the elements inside against water and dust to prolong its service life.

5 Levels Sound Volume Adjustable: adjustable from 0-110dB, the mute mode can offers user with better usage experience.

Touch Button: the interval between two bells is about 20 seconds, no need to keep pressing the button all the time.

SOS Caller Function: With a hanging hole for being connected to neck strap or wrist strap, elder people can use it as a caller for help.

Specification:
Material: Plastic
Waterproof Grade: IP55
Working Temperature: -30℃ to +70℃
Working Distance: 300m (without barrier)
Working Frequency: 433.92MHz
Sound Volume: 0-110dB (5 levels adjustable, with mute mode)
Receiver Voltage: 110-260V / 50-60Hz
Certification: CE, ROHS, FCC, PSE, TELEC 
Transmitter Battery: 12V 23A alkaline zinc-manganese battery (built-in)
Size: 
Receiver(length*width*thickness): 2.36*2.36*0.59inch
Transmitter(diameter*thickness): 3.07*1.97inch

Package list:
1 x Receiver
1 x Transmitter
1 x Adhesive Tape
1 x Manual
1 x Screwdriver