Mistake-proof stem selection - set includes five wheels and 10 stem fasteners (5 each: 3/8"D x 1"L and 7/16"D x 7/8"L) for all metal-base chairs
Full hood design - 1-1/2"D oversizedneck, weight rated 100 lb./wheel
Determine correct stem diameter by removing a caster from the leg of your chair base. Match diameter of existing stem and insert into caster body- Discard the other five fasteners
Comments about Global Lumbar Pump Fabric Managers Mid-Back Chair, Burgundy:
This chair has no seat adjustments and by the time you pump up the lumbar support you are being tilted toward the floor. After 1/2 day or less the lumbar looses its air pressure and you have to pump it up again. The height adjustment will not go tall enough for my desk and I feel my desk is at my chest. RECOMMEND YOU KEEP LOOKING FOR A BETTER CHAIR WITH MORE ADJUSTMENT. TERRIBLE OFFICE CHAIR - UNLESS YOUR THE BOSS AND CAN SET BACK WITH YOUR FEET UP TO KEEP YOU FROM FALLING IN THE FLOOR.