... case Swivel caster1.Material:high quality steel and rubber2.Color:caster base is coated with bule zinc,nickel free,enviremental friendly ... details,please contact the customer services.4.Advantages:This swivel caster is made for the very large flight case,duo to ... the corrosive liquid.6.We can supply our customer with many different sizes and typles caster,just please make me know your ...