Zhitaoxun 28 Bolt and Nut Identifier Gauge Nut and Bolt Thread Checker 14 Metric & 14 Standard Ruler with Inches and Centimeters On Both Sides: Amazon.com: Industrial & Scientific
Dasunwat Nut and Bolt Thread Checker, 14 Metric & 14 Standard Sizes, Identibolt Bolt Nut Identifier