Recommended use: indoor
Length of laser line: Up to 20 ft (6 meters)
Laser class: 
US version*Class IIIA EU
Version*Class IIIR
Operational area: Up to 20 feet (60 meter) of visible light, indoors 
Power supply: 2 TYPE AAA-1.5 volt batteries
Battery life: 40 hours of continuous use with alkaline batteries

Accuracy: Direct laser beam:
+/-1/2" at 20 ft (+/-13.0mm at 6 m)
Horizontal / vertical / cross line:

+/-3 mm at 3m
Laser spot:

+/-5 mm at 10 m