Sealey Metric/Imperial Nut & Bolt Thread Checker

Amazon

SIMPLE - With 14 Imperial and 14 Metric sizes, this Thread Checker accommodates a wide range of common nut, bolt, and screw sizes, making it very versatile. PRECISE - Designed to accurately identify and measure threads, ensuring you select the right fastener every time, whether you are working with fine or coarse threads. DURABLE - Made from a premium alloy, the Thread Checker will give long lasting performance. PORTABLE - Lightweight and compact. USER FRIENDLY - Clearly labelled with easy-to-read markings, male and female versions of each size are easy to identify. INCLUDES - Length checker on either side of board - one edge is metric and the other is imperial. SIZES: Imperial; 6-32C to 1/2-20F, Metric; M4-0.7, M5-0.8, M6-1.0, M7-1.0, M8-1.0, M8-1.25, M10-1.0, M10-1.25, M10-1.5, M12-1.25, M12-1.5, M12-1.75, M14- 1.5, M14- 2.0

Zoro Tools

Accurately measures and identifies threads. 14 Imperial (6 to 1/2") and 14 Metric (M4 to M14) sizes in coarse and fine pitches. Easy-to-read markings make male and female versions of each size easy to identify.