The Bosch GLL50-20 is a professional-grade self-leveling cross-line laser designed for precise layout and alignment tasks. It projects highly visible horizontal and vertical red lines with a working range of up to 50 feet and an accuracy of ±5/16 inch at 30 feet. Built for jobsite durability, it features a full rubber overmold housing and an IP55 rating for dust and water resistance. The integrated Smart Pendulum System allows the unit to self-level, indicates out-of-level conditions by blinking, and automatically locks for secure transport when powered off. This versatile tool offers dual power flexibility, operating on standard AA batteries or an optional 3.7V Lithium-Ion battery (sold separately). It includes an integrated magnetic mount and 1/4-20 tripod threading for easy positioning on various surfaces