Mistakeproof stem selection - includes 5 wheels and 10 stem fasteners (5 each 3/8"D x 1"L) (5 each 7/16"D x 7/8"L) for all metal-base chairs
Full hood design - 2"D oversized neck, weight rated 100lb. per 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™ Traditional Black Leather Executive High-Back Chair w/ Mahogany Wood Finish:
This chair looks greats and is easy to assemble BUT it, by default, sits forward. It leans forward and for that big reason, it's uncomfortable and subsquently isn't that ergonomic in my opinion. I mean, you have to make sure your feet are planted in front of you because you feel like your falling foward. Plus, to lean back, you have to really make an effort to 'push' yourself back. Even if you loosen that seat adjustment all the way out (very loose), and you still have to put pressure to lean back. Weird! This chair replaced a "Lane Dream Teakwood Leather Executive Chair with Walnut Accents". I thought that chair was 5 times more comfortable than this chair and it cost over a $100 less!!! But, that Lane had quality issues with the hardware under the chair (Staples stopped carrying it even). If you don't mind spending $400 for a beautiful, well built executive chair that tilts forward, then this is your chair. Otherwise, pick something else. This chair is going back tomorrow!!