Lap HD Diode line laser, Green, up to 10m length, 15mWLasers of HY series with green laser beam are used, when visibility of red lasers is no longer sufficient. This may occur on adverse surfaces (e. g. red or black, wet stone) or bright ambient illumination (sunlight). Green light has a visibility about five times higher compared to red light, because human eyes have their maximum sensitivity in this wavelength area. The robust housing made of stainless steel protects laser, electronic circuitry, and