... :SUS SWC CU 3.Standard:ISO9001 ROHS SGS 4.Customizable battery contact springs1>9 years of experience in producing springs2>design as ... copper, beryllium copper. Alloy steel has 60Si2MNA, 60Si2CRVA, 55CrSiSurface treatment plate gold, silver, white, red yellow, blue, green, purple, black, etc ... spring length, which ensured the spring quality stable and precise. Battery Contact Compression Springs