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Silver metal office chair gas cylinder with black piston rod, 50mm outer diameter, 28mm inner diameter

BFKK

BFKK Class 4 Hydraulic Pneumatic Piston 50mm 28mm 5.5in 1000lbs

SKU CH-ATPH-7HN5D

Heavy-duty Class 4 chair cylinder supports 1000 lbs with 5.5 inch adjustable stroke, 50 mm outer and 28 mm inner diameter, and silent 360° rotation

  • TypeChair & Furniture Accessories
  • SGS & BIFMA certified safety tested to 100000 cycles
  • Supports up to 1000 lbs with solid steel construction
  • Adjustable 5.5 inch stroke from 11.4 to 16.9 inches
  • Universal 50mm outer and 28mm inner diameter fits most chairs
  • Silent 360 degree rotation for smooth, noise-free operation

Heavy-Duty Class 4 Piston

This SGS and BIFMA certified hydraulic pneumatic piston is built from solid steel for office chair repair. It supports a maximum load of 1000 lbs and has passed 100000 rotation, push, pull and impact test cycles without functional loss.

Fits Standard Chair Bases

The universal 50 mm outer diameter and 28 mm inner diameter suit most executive, salon, work chairs and rolling stools. Buyers with non-standard or proprietary cylinder dimensions should verify compatibility before ordering.

5.5 Inch Adjustable Stroke

The cylinder extends from 11.4 inches to 16.9 inches, providing a 5.5 inch height range for flexible seating positions. Chairs requiring a longer or shorter travel range will not achieve the desired adjustment with this unit.

Highlights

  • SGS & BIFMA certified safety tested to 100000 cycles
  • Supports up to 1000 lbs with solid steel construction
  • Adjustable 5.5 inch stroke from 11.4 to 16.9 inches
  • Universal 50mm outer and 28mm inner diameter fits most chairs
  • Silent 360 degree rotation for smooth, noise-free operation

Specifications

TypeChair & Furniture Accessories

Questions about this item

What chair base diameter do I need for the 50 mm outer cylinder to fit?

The piston's outer cylinder measures 50 mm, so your chair base must accept a 50 mm diameter stem for a secure fit.

Will the 28 mm inner cylinder work with my existing chair mechanism that uses a standard 1.1 inch stem?

Yes, the inner cylinder is 28 mm (1.1 inches), matching the common stem size used on most office and salon chair mechanisms.

How can I verify the 5.5 inch travel is functioning correctly after installation?

Measure the fully extended length at 16.9 inches and the compressed length at 11.4 inches; the difference should equal the stated 5.5 inch adjustable range.

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