1.Gas Spring / Air Spring /Gas Lift Chair / Gas Cylinder / Gas Strut for Office Chair /Gas Parts for Bar Stool / Table2. 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 / Chrome4.bottom treatment:curl edge/electric welding5.Standard: Class 2/ Class 3/ Class 46.SGS BIFMA X5.1(100,000 Times Testing)7.Pressure(N):300--4508.Button Color: White / Black / Orange / Blue / Gray / Green9.Warranty/Gurrantee: 5years10.Management System of our company:OEM Service11. Certificate:ISO9001 Certificate,SGS and BIFMA