eBay

1.RELIABLE - Entire support bracket are made of high grade steel&wheels surface are made of high quality artificial rubber providing years effortless rolling and durability. Precision ball bearings in the caster swivel and provide smooth, easy rolling while causing no squeaky sounds or noise of any kind.
2. HEAVY DUTY AND ULTRA STRONG - The caster wheels have been rigorously tested, the heavy duty design supports up to 550 lbs as a set of 5.
3. SAFE FOR ALL FLOORS - Stop damaging your expensive hard wood floors. Many chair wheels use cheap, low quality materials that destroy your flooring. We don't. Encased with soft, polyurethane material our style wheels are guaranteed not to scratch or leave marks on any surface.
4. UNIVERSAL - Fit most office chair models available except IKEA brands., standard stem diameter: 7/16"(11mm), stem length: 7/8"(22mm)
5.USER FRIENDLY - DIY Easy pull and snap installation and Require No Tools to Install,Quality problem Money Back Guarantee.