The MILWAUKEE Green Cross Line Laser provides 8 plus hours of runtime for all-day brightness and is powered by (4) AA batteries. The high-intensity laser beams allow you to see the green lines up to 100ft for fast and accurate leveling and alignment. The integrated magnetic bracket features amplified rare earth magnets for a stronghold on metal surfaces while the screw and nail hang holes make setup easy and efficient in any environment. The Milwaukee Green Cross Line Laser is covered by a two-year warranty.