China Stainless Steel BIFMA X5.1 En 1335 DIN 4550 TUV LGA Lockable Adjustable Class 4 Master Spring Office Chairs Gas Spring, Find details about China Gas Spring, Gas Lift from Stainless Steel BIFMA X5.1 En 1335 DIN 4550 TUV LGA Lockable Adjustable Class 4 Master Spring Office Chairs Gas Spring