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, Black:
The chair is very comfy. The lumber, tilt, and height adjustments help make this chair perfect for everyone. The couple of things that I didn't like were the fact that the lumbar support pump hangs awkwardly under the chair and that the fabric tends to attract and hold lint and hair.
Comments about Global Lumbar Pump Fabric Managers Mid-Back Chair, Black:
Padding is thick, but a bit firm. Build quality appears to be typical. Angle of back does not adjust (like most chairs). I work at a computer and did not install the spacers due to the angle it gave the chair. Like so many, the back angled away to where you couldn't use it. I loosened all the bolts, pushed the back and seat toward each other as much as possible and then tightened it. That did angle the back forward to what may work out as an acceptable amount. Haven't decided if the lumbar support is useful or not.
Comments about Global Lumbar Pump Fabric Managers Mid-Back Chair, Black:
I use the chair for my computer use and at my home desk where I spend a lot of time writing. I do like the chair, I am just surprised that the "Lumbar Pump" doesn't really do anything for the lumbar support. In which case the back of the chair leans back, rather then meeting your back for support, plus it is rather hard for sitting at long periods of time.