The Moore & Wright Engineer's Levels have a precision ground cast base with a V-groove for location on cylindrical work. Each level is fitted with a main, cross and plumb vial and the main vial is protected by a rotating shroud. The solution in the vials maintains colour and fluidity under all workshop conditions and the main vial has a sensitivity of 1 minute.The Moore & Wright ELS Engineer's Levels have the following specification: Length: 165mm (6.5in).Width: 34mm (1.34in).Height: 46mm (1.81in).Resolution: 0.3mm per metre (0.0035in per foot).Additional Information:Size (mm): 165Size (in): 6.1/2Resolution (mm): 0.3Resolution (in): 0.0035