Precise and easy-to-use internal and external thread identifiers for nuts and bolts. Steel identifiers are strung on a wire lanyard. Permanent, easy-to-read size markings are laser etched into each stand off. Shatterproof, color-coded polypropylene gauge divider beads allow recognition between inch and metric strands. SPI Miniature Thread Detective Screw Pitch Gage. 9 Inch thread standards: 1-64, 1-72, 2-56, 2-64, 3-48, 3-56, 4-40, 4-48, and 5-40. 12 Metric thread standards: M1.2x0.25, M1.6x0.2, M1.6x0.2, M1.6x0.35, M2x0.25, M2x0.40, M2.5x0.35, M2.5x0.45, M3x0.35, M3x0.5, M3.5x0.35, and M3.5x0.60.

SPI Thread Detective: Mini inch/metric Screw Pitch Gage for Nuts & Bolts