KF2 Remote Key finder

Frequency: 433.92MHZ
Sound: 75DB
Rmote controller:8.5X3X1CM
WT:38.5g (battery included)
Battery:CR2032 1pc 3v
Receiver: 4.5X2.8X1.1CM
WT:13.5g(battery included)
Battery:CR2032 1pc 3V
Color box package
Working distance: 25-40meters.

Stick the remote controller on the wall, and the receiver with keys or the article you always can't find, when you can't find them, just push the corresponding button on the remote controller, and the receiver will sound alarm right away.(it can find the lost thing in a 400 square meter house)
The alarm will last for 4 seconds then stopped automatically.