Kapro 105-24 Topgrade Box Level, 24-Inch Box-style gradient spirit level for determining slope from 0% to 2% as well as vertical plane Shockproof, solid acrylic vialsthree or five gradient and one plumbresist breakage and provide clear readings Sensitivity is 0.5 mm/m (0.0005"/inch) for precise readings Milled leveling surface for accuracy Aluminum body for light weight and corrosion resistance with end caps that help absorb impacts