Comparison : Item # 1317-12-342, 3/16" Tube O.D. (3/8-24 Bubble) British Metric Union
Item # 1317-12-343, 3/16" Tube O.D. (10MM) European Metric Union
Item # 1317-12-344, 3/16" Tube O.D.(M10-1.0 Inverted) Japanese Metric Union
Item # 1317-12-345, 6mm (M12-1.0 Bubble) GM Metric Union