The Kapro 893 allows carpenters and drywall contractors to mark exact 90° lines over a long piece of wood or drywall for free-form cutting. Instead of using traditional tools, which demand repeat measuring and marking, you can just slide the T-Laser on the edge of the board, and cut along the 90° laser line. You don't even need to switch it on - the power switch is pressure-activated as you slide onto the board. The 893 T-Laser fits on all standard drywall, plywood, and composition boards inch (6.4 mm-15.9 mm). With a clip-on spring grip, 90° aluminum T-Square angle, and a molded rubber case that fits comfortably in your hand. The size of a standard tape measure, it can clip on to your belt. Can also be used as a single dot straight laser by manually turning the on/off switch and placing on top of any surface.