... 3) Certificate: ISO/TS16949 4) High quality, good price Steel Coil Spring: 1. Material: Steel, 251A58 – Silicon Manganese ,60Si2Mn2.Surface:Shot Peened ... black/Powder coated3. Size: According to customers' request 4. the coil compression spring is resistance to both high/low temperature and high pressure5 ... : ISO9001:2000/TS169496. High quality, Competitive price, Fast delivery Steel Coil Spring