Inch Screw Checker - Instant Identification of #1 - 5/16" Screw Threads
Screw Check'r, Metric Screw Checker, by Brownells, determine screw size, diameter, length, tap series, body drill size and tap drill for machine screws
Screw and Bolt Identifier Board - Etsy
Inch Screw Checker: Instant Identification of #4 - 1/2" Screw Threads
TIMCO | Screw Measuring Information
Amazon's iPhone app adds AR feature for identifying and buying small nuts and bolts - The Verge
How to determine the screw size (No.)? - Home Improvement Stack Exchange
METRIC SCREW AND BOLT THREAD IDENTIFIER / CHECKER W/ THREADED HOLES MADE IN USA | eBay