Johnson® box beam levels are built Job Site Tough so you know the solid block acrylic vials won''t break and the anti-shock end caps keep the level frame protected for years of accurate use on the construction site or in the home. This Aluminum Box Level features SurroundView® Vials that reflects ambient light for easy read in dimly lit work environment. Solid block acrylic vials won''t fog, leak or break. Impact resistant abs end caps for durability. Abs hand grips for comfort.• Length: 24"• Aluminum box beam level• Three vials: read plumb, plumb & level• SurroundView® reflects ambient light for easy read• Solid block acrylic vials won''t fog, leak or break• Impact resistant abs end caps for durability• Abs hand grips for comfort• Accuracy up to .029 degrees 0.5 mm/m) in the standard position, .044 degrees 0.750mm/m) in the inverted position.