The Alvin Screw Data Selector is a must-have tool for machinists, engineers, draftsmen, fabricators, mechanical designers, builders, and many others. A handy and useful guide, it is equipped with dimensions and full size data of nuts, bolts, screws, threads, drills, holes, and more. It also includes wrench clearance information and tolerances for drilled holes. With a fraction/decimal equivalent chart, it also functions as a calculator.
The Alvin Screw Data Selector, with its slide chart design, is a quick and reliable reference. It measures 5"W x 10"L and is easy to carry around anywhere to provide solutions for all measuring and drawing needs.