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