Herman Miller Aeron Compatible Soft Caster Wheel for Hardwood Floors - 5 Casters<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Fits Herman Miller Aeron and Mirra. Twin wheel for easy mobility on hardwood， ceramic and marble as forgiving on hard wood floors.</li><li>Standard 7/16"x7/8" (11mm x 22mm) wire grip ring stem (universal to most chair bases)</li><li>Will not scratch or scuff floors if floors are kept clean - Soft nylon wheel - Ideal for use on hard surfaces and hardwood floors</li><li>Dual wheel polyurethane casters are softer than your standard caster， Casters rotate full 360 degree for smooth movement</li><li>Simply pull out old casters and hammer in new ones with rubber hammer or by hand</li></ul></div><img src="http://ecx.images-amazon.com/images/I/41qEfckkSgL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/41CYB62cbuL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/31%2BLpWpe4VL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/31bYKh8t8RL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/21kNr76ZzqL.jpg" noproxy>