The Bosch Self-Leveling Cross-Line Laser (GLL30) is a compact leveling and alignment solution with top-notch accuracy and one switch operation. It features a Smart Pendulum System, which self-levels and is capable of locking the projected lines at any angle for a wide variety of layout applications.The cross-line projection is visible up to 30 feet. The unit includes a flexible mounting device that can clamp to practically any surface for maximum versatility and microfine height adjustments.