The Thread Detective is a precise and easy-to-use thread identifier for both nuts and bolts, consisting of gliding gauges conveniently assembled onto a wire lanyard. It is especially well suited for distinguishing between similar inch and metric threads. Our unique Thread Identifiers (aka thread checkers) are available in Metric, English Standard, and a combo of Metric and English Standard. For your convenience we provide extra-long wire rope for those hard to reach places, as well as loops on each end for convenient hanging. Inch Thread Identifiers contain nut and bolt sizes of 1-64, 1-72, 2-56, 2-64, 3-48, 3-56, 4-40, 4-48, 5-40Metric Thread Identifiers contain nut and bolt sizes of M1.2x0.25, M1.6x0.35, M1.6x0.20, M1.8x0.35, M2.0x0.40, M2.0x0.40, M2.0x0.25, M2.5x0.45, M2.5x0.35, M3.0x0.50, M3.0x0.35, M3.5x0.60, M3.5x0.35.