Bosch GPL3 3-Point Laser Alignment with Self-Leveling Plumb and Level Point Projection. Accurately transfers and aligns level, plumb, 90-Degree and grade points Patented Diamond-Cut Beam Splitter. Single diode projects all points for superior accuracy Smart Pendulum Leveling System. Self-levels, senses and indicated out-of-level condition, locks when switched off Robust Over-Molded Housing. Water and Dust Proof to ensure years of dependable operation Pocket-Sized. Only 4-1/8-Inch (105 mm) tall; pouch fits on tool belt. Also features an Easy Access Battery Compartment Class IIa laser product, &lt;1mW power output