Comparison : Item # 1317-12-260, 3/16" British (3/8-24 Bubble Thread) Inverted Flare Metric Tube Nut Zinc
Item # 1317-12-261, 3/16" European (M10-1 Bubble Thread) Inverted Flare Metric Tube Nut Zinc
Item # 1317-12-262, 3/16" Japanese (M10-1 Inverse Thread) Inverted Flare Metric Tube Nut Zinc
Item # 1317-12-263, 3/16" Domestic (1/2"-20 Inverse Thread) Inverted Flare Metric Tube Nut Zinc
Item # 1317-12-264, 3/16" Domestic (9/16"-18 Inverse Thread) Inverted Flare Metric Tube Nut Zinc