... 3.springs for doors 4.professional work on cutting rolling shutter roll-up door spring A high-carbon steel that ... hardened, AISI 1070 also performs well in hand and machine tool applications.Heat treatment is carried out mainly for ... Hardness as per client’s requestForms: Coils, Sheets, stripsApplications: roller shutter, rolling shutter springRaw Material: Baosteel CK67,SAE1065,CS70I.D. Coil: < 20”, ...