Made from heavy gauge stainless steel, and used for measuring the gauges of steel wire and hot and cold rolled sheet steel. Metric dimensions are recorded on one side and SWG (Standard Wire Gauge) marking on the other. SWG - mm - inches:- 36 - 0.19 - 0.0076, 35 - 0.21 - 0.0084, 34 - 0.23 - 0.0092, 33 - 0.25 - 0.01, 32 - 0.27 - 0.0108, 31 - 0.30 - 0.0116, 30 - 0.32 - 0.0124, 29 - 0.35 - 0.0136, 28 - 0.38 - 0.0148, 27 - 0.42 - 0.0164, 26 - 0.46 - 0.018, 25 - 0.51 - 0.02, 24 - 0.56 - 0.022, 23 - 0.61 - 0.024, 22 - 0.71 - 0.028, 21 - 0.81 - 0.032, 20 - 0.91 - 0.036, 19 - 1.02 - 0.04, 18 - 1.22 - 0.048, 17 - 1.42 - 0.056, 16 - 1.63 - 0.064, 15 - 1.83 - 0.072, 14 - 2.03 - 0.08, 13 - 2.34 - 0.092, 12 - 2.64 - 0.104, 11 - 2.95 - 0.116.