There's an insane mix of gauges for wire, needles and drill bits in the U.S. SWG (standard wire gauge aka British standard wire gauge) isn't used much ... guitar strings is about it. SWG is not the same as AWG (American wire gauge aka B & S [Browne and Sharpe] gauge), used for electrical wiring. Then there's BWG (Birmingham wire gauge aka Stubs iron wire gauge) used for hypodermic needles and iron (not steel!) wire. There's the crazy number/letter drill gauges. And the W&M (Washburn and Moen) gauge used for steel wire, which is not to be confused with Stubs steel wire gauge. Finally, there is U.S. standard gauge for sheet metal, which is not to be confused with American wire gauge.
Help!
Mike in California