The laser point and vertical line are measured simultaneously from the front to the left and right tilt. Laser light, so it does not shake by wind. The light output is less than 1 mW and a class 2 laser product. The magnetic damper will instantly stop in about 3 seconds. Accuracy: ±0.04 inches (1 mm) or less / 13.9 yd (4 m); Automatic correction range: ±3.5 °; Width: 2.4 inches (60 mm); Depth: 3.7 inches (95 mm); Height: 6.7 inches (170 mm); Weight: 13.8 oz (390 g); Power supply: Vertical measurement when raising of building building.