1.Gas Lift,Spring,Cylinder,Strut for Chair,Table 2.Black,chrome Surface 3,SGS BIFMA 4,ISO9001 Certificate 5,OEM Service 1 ... , Gas Spring / Gas Lift / Gas Cylinder / Gas Strut for Office Chair ... : Black / Chrome4. Standard: Class 2 / Class 3 / Class 4 5. SGS BIFMA X5.1(100,000 Times Testing)6, Pressure(N ...