The instrument enables the laser to arrive each direction,can facilitate accurately looks for the accurate work goal. Wavelength of laser:635nmACCURACY:±5mm/6mFan ANGLE:120-140°Operative distance: 6mPower Supply:2AA Batteries 3V class III aUser in inside and outside the room to repair,installs the windows and door,the cabinet,pastes the ceramic tile,the floor tile,the suspended ceiling and so on. ...