Bosch 3-Point Laser Alignment with Self-Leveling GPL 3 ACCURACY: The Bosch GPL 3 features plumb and level point projection to accurately transfers and align level, plumb, 90-Degree and grade points. It offers accuracy of +/- 1/4 In. at 100 ft. and eliminates the need for a standard plumb bob. PRECISION: Featuring the Bosch-Patented Diamond-Cut Beam Splitter  a system that allows a single diode to project all laser points for superior accuracy and precision SELF LEVELING: With Boschs Smart Pendulum System the alignment laser self levels and indicates out-of-level condition and locks when switched off. DURABLE: The Bosch GPL 3 is durable and tough with a robust over-molded housing. Its water and dust proof to ensure years of dependable operation. PORTABLE: At only 4-1/8-Inch (105 mm) tall; the GPL 3 is pocket-sized and portable. The pouch fits on your tool belt and also features an Easy Access Battery Compartment Class II laser product, &lt;1mW power output