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 Office Star SPACE® Air Grid Deluxe Mesh Manager's Chair, Black:
This is a great chair. This is my primary work chair and it seems to be holding up well with daily use. Over time, it does tend to squeek a little, but overall, I think it is a great product.