Johnson's 40-6515 Self-Leveling Leveling Rotary Laser is designed for accomplished homeowners and accomplished tradesmen working both indoors and outdoors. Preparing this rotary laser level for use is easy simply turn it on and unlock the transportation lock and the laser levels itself in both the X or Y axis. This rotary lasers project a red beam of light 360°. It's versatility allows for three rotational speeds of 200, 300 & 400 RPM. Slower rotational speeds enhance beam visibility while the higher speed is preferred for outdoor use. For maximum versatility this rotary laser can be used horizontally or vertically. In the horizontal plane the laser is self-leveling and in vertical applications it is manually leveled. The durable high-impact composite housing is JobSite Tough™. The lasers' split beam feature establishes a 90° angle. The enclosed beacon protects inner mechanism from water and dirt. Illuminated vial for easy vertical set-up. Integrated vertical bracket for vertical applications.