Metal screw checker measures 2.0mm (.079") thru 7.0mm (.276") diameter screw sizes. Measures lengths up to 60.0mm (2.36"). Indicates tap series, threads per inch, and clearance drill and tap drill size required. Will straighten bent screws, clean rusty or damaged threads, and hold screws while cutting, drilling or altering the head. Made of heavy gauge satin chrome plated stee.