Auto suspension coil Springs 1.Material:carbon steel;spring steel;stainless steel,alloy steel. 2.Wire Dia.:0.01mm-10mm Auto suspension coil Springs1.Material:carbon steel;spring steel;stainless steel,alloy steel.2.Wire Dia.:0.01mm-10mm3.ISO9001 certificate.4.We can do OEM.5.Surface treatment:Zinc,Nickel,silver,golden,powder coating.6.Applications: Automotive Auto suspension coil Springs