Gas spring or gas strut for office chair 1.Pass SGS test 2.100000 times ... .OEM service 1.Gas Lift,Gas Spring ,Gas Cylinder,Gas Strut for Office Chair,Bar Stool,Table 2. Stroke(mm): 80 ... ,120,140,160,230,260,3303. Surface: Black,Chrome 4. Standard: Class 2,Class3,Class 4 5. SGS BIFMA X5.1 ... years 9. OEM Service10.ISO9001 Certificate. gas spring or gas strut for Office Chair