Katu Wheels for Office Chairs Casters - Replacement for Laminate, Hardwood, Carpet. Set of 5 Black Wheels for office chairs replacement for floors, hardwood, laminate, vinyl flooring, mats and more. The office chair casters come with the standard 7/16" (11mm) stem, fit most office and desk chairs. Heavy duty, set of 5 supports 550 lbs making it the best replacement for your desk or office chair. 5 years warranty, eliminates the need of office floor mats. Install in minutes with no tools. smooth movements, 2 3/8 inch wheels lubricated for easy movement with a layer of rubber PU.