Plugs > 12 gauge ~ 2.0mm > 8 gauge - 3mm > 6 gauge ~ 4mm > 4 gauge ~ 5mm > 2 gauge ~ 6mm > 0 gauge ~ 8mm > 5/8 inch ~ 16mm > 1-3/8 inch ~ 35mm > 1-5/8 inch ~ 41mm > 2 inches ~ 51mm