... complete range of heavy duty and high performance hot coil compression springs made from high grade metals. The clutch ... Spring, Extension spring, Torsion Spring, Battery Spring, Power spring, Coil spring, leaf spring, suspension spring, etc. 2) Main material: ... silver-plated, copper-plated, tin-plated and nickel-plated; Painted, spraying powder, coloring 5) Eco-friendly products:EU standards ...