1.Gas Spring / Air Spring /Gas LiftChair / Gas Cylinder / Gas Strut for Office Chair /Gas Parts for Bar Stool / Table 2. Stroke(mm): 40/ 60 / 80 / 100 / 120 / 140 / 160 / 180 / 200 /230 / 260 / 330,Etc..(We can specially customized for your company's needs) 3. Surface: Black / Chrome 4. Standard: Class 2/ Class 3/ Class 4 5.SGS BIFMA X5.1(100,000 Times Testing) 6, Pressure(N):300--450 7, Button Color: White / Black / Orange / Blue / Gray / Green 8, Warranty/Gurrantee: 5years 9. Management System of our company:OEM Service 10.Certificate:ISO9001 Certificate,BIFMA,SGS