FC 21-3050 Tire Foam Filled Grey Drive Wheel Assembly for Factory Cat and Tomcat Floor Scrubbers. A 9" diameter foam filled drive tire with bolt-on wheel. This wheel may be listed as an optional wheel with our FC 21-3060 (Pneumatic), and FC 21-3010 (Black) tire. Commonly used as a drive tire/wheel assembly on Factory Cat MiniMag series. Please refer to your parts manual for the proper application. Most models require two wheels. Priced Each. Replaces Factory Cat 21-3050. Our Part Number FC 21-3050