SlipStick 3 in. Black Rollerblade Office Chair Caster Wheels (5-Pack) CB690 - The Home Depot
Amazon.com : The Original Rollerblade Office Chair Wheels (As Seen On PBS) - Incredibly Smooth & Quiet Rolling Casters - Safe for Hardwood Floors & Carpet - Easy Installation with Universal Fit : Office Products
The Office Oasis Rollerblade Office Chair Wheels for Hardwood