Miller XMT 350 CC/CV Auto-Line Owner's Manual page 58

Notes
MATERIAL THICKNESS REFERENCE CHART
24 Gauge (.025 in.)
22 Gauge (.031 in.)
20 Gauge (.037 in.)
18 Gauge (.050 in.)
16 Gauge (.063 in.)
14 Gauge (.078 in.)
1/8 in. (.125 in.)
3/16 in. (.188 in.)
1/4 in. (.25 in.)
5/16 in. (.313 in.)
3/8 in. (.375 in.)
1/2 in. (.5 in.)