The DW083K 3 Beam Laser Pointer Includes A Single Lever Power Switch That Locks The Pendulum In The Off Position For Added Durability And The Built-in Magnetic Pivoting Bracket Mounts Easily On Metal Surfaces.Applications: Steel Track Installation Curtain-wall Installation Locating Overhead Anchor Locations Locating Plumb Drilling Locations For Vertical Pipe Locating Overhead Anchor Locations Plumbing Of Door Jambs Checking Forms For Plumb Floor To Ceiling Transfer Includes: Kit Box 4 AA Batteries Self-levling Point Laser Is Accurate To ±1/4" @ 100' Single Lever Power Switch Locks Pendulum In The Off Position For Added Durability Built-in Magnetic Pivoting Bracket Mounts Easily On Metal Surfaces Integrated Track Clearance Enables Users For Fast And Accurate Bottom And Top Track Installation Overmolded Housing Helps Maintain Calibration Under Job-site Conditions Focused Laser Beam Keeps Dot Size Small Over Longer Distances For Improved Accuarcy And Visibility