The function of checking cable：The"scanner"will help you to check and find the twin cables in need among so many cables in no tine
The function of verifying cable：With the verifying function of the "scanner"it will be very fast the basic physical connecting feature of open and short and cable sequence status on the cables below
Circuitry status testing：
a. How to check DC and confirm positive & negative polarities              
b. Ring flowing signal checking
c. Open and short circuit testing
The function of regulating precision：The sensitivity is changed by adjust the volume switch, when receiver's sound is small or big, Adjust volume switch, the sound will changed
The function of earplug：The hole for earphone, when voice of environment is not clear, please use earphone
Electricity：Emitter≤20mA，Receiver≤25mA
Power specification：DC，9V terrace battery
Distance of signal transmission：≥3km
Safety：use safe
Appearance dimension：265×165×38mm   Weight：0.375kg