... ,Zinc plated 3,Material:low carbon steel tube 4,Use:auto brake assembly O.D(mm) Thickness(mm) 3.180.7 4 ... .000.7 12.000.7 12.700.71,Use:automobile brake system2,Standard:ASTM,DIN,UNI,GB3,Material:low carbon steel ... thickness:0.5mm~0.7mm6,Outer diameter:3.18mm~12mm Auto Metal Brake Tube