Single Flare > 6 gauge ~ 4mm > 4 gauge ~ 5mm > 2 gauge ~ 6mm > 1 gauge ~ 7mm > 00 gauge ~ 9.5mm > 13/16 inch ~ 20mm > 1 inch ~ 25mm > 1-1/4 inch ~ 32mm > 1-3/4 inch ~ 44.5mm > 1-7/8 inch ~ 48mm