It is a stainless steel having a 17Cr-7Ni type composition and can obtain high strength by cold working. It is used for railroad vehicles, belt conveyors, springs, bolts, nuts, etc. often used for spring. Has high hardness. It is a material with a higher work hardening than SUS304, but lower in corrosion resistance. Due to its low chromium content, it is susceptible to stress corrosion cracking.