TAD Universal Reference Calculator

If you're a mechanical engineer, draftsman, or PCB designer, this is a handy tool to have on hand. This little slide tool puts a wealth of mechanical info at your fingertips, including but not limited to, rivet data, standard screw data, SAE thread data, hole tolerances, sheet metal & wire sizes, much much more. These are hard to find. High bidder pays $2 shipping. Thanks for looking.