gas spring,chair gas spring,office chair gas spring,gas cylinder,gas strut gas spring,chair gas spring,office chair gas spring,gas lift,gas cylinder,gas strut 1. Stroke option (mm): 65/85 / 100 / 120 / 140 / ... . Surface finishment: powder coating/chromed4. Bottom Type: Folded type or welded type or with deeper taper for high chair bases5. Certificate: ISO9001 + SGS BIFMAX ...