Manual says to use drill bits as gauge but numbers?

google is a wonderful thing LOL .... ^^^ beat me to it ^^^^ , ill leave mine up anyways


Drill Bit to Wire Gauge Conversion Chart

http://www.riogrande.com/Content/Drill-Bit-to-Wire-Gauge-Conversion-Chart-CG-html?Pos=3


http://www.custompartnet.com/drill-size-chart