This steel gauge is a quick all-in-one reference for identifying screw diameter, length and thread, tap drill size, and through-hole drill clearance size. Each reference hole is precisely tapped for direct screw threading to ensure proper identification.
The Imperial version gauges common fastener sizes from #1 through 5/16", and threads per inch from 72 to 18; the metric version measures diameter from M2 to M7 and pitch from 0.25 to 1.00. A useful tool for quickly identifying threaded fasteners, wood screws and tapping screws, it includes instructions and a handy decimal equivalent chart. Made in the USA.