This gas cylinder fits  DXRacer Tank and Hercules Big & Tall Chair from Flash Furniture and other chairs, as replacement Gas Cylinder.  Large Super Heavy Duty. Make sure the diameters match your existing cylinder, as there are several sizes for this series chairs

• Larger than standard. Heavy duty pneumatic gas cylinder lift for office chair height adjustment
• Typically installed on chairs rated up to 500 lb.
• 3.5” stroke (seat travel from lowest to highest settings)
• Gas spring diameter 1.5” (standard cylinder are 1.1")
  
• Chrome plated column is 2.7" in diameter (standard is 2")
  
• Dimensions when fully compressed: 10”. Fully extended: 13.5”
• Under base extension: 0.5"
  
• Exceeds BIFMA standards
• Cylinder shipped completely assembled ready for use