Product Description 1. Spring Specification Dimension: 1. Material: high carbon spring steel; music wire; stainless steel(SUS301,302,304,316,201,202);alloy steel(60Si2MnA,55CrSi,50CrV,60SiCr8A);copper wire ,iron wire , 2. Wire Diameter: 0.1-65.0mm3. Surface treatment: become black, Zinc/ Nickel/Silver/Golden/Tin plated ,polishing ,anti-rust..