Bosch LR 2 Professional Laser Receiver for easy alignment of the laser beam plane. It also offers visual (display and LEDs) and audible signals, for working in various lighting conditions. If needed it can be easily attached to a staff. Suitable for use indoors or outdoors. Specifications: Range: 5-50m. Accuracy (Fine/Rough) : +- 1mm/+- 3mm. Suitable for: GLL 2-50, GLL 3-50. Power: 1 x 9V 6LR61 Block (supplied) Dust and Splash Protection: IP54. Weight: 270g.