Antimicrobial Nonmarking Rubber Tread on Plastic Core Wheel 325 lb Load Rating 300 to 999 lb Load Rating Range 4 in Wheel Dia 1 1/4 in Wheel Width Thermoplastic Rubber Wheel/Tread Material Firm 85-95 Shore A Precision Ball Donut Tread Shape 7/16 in For Axle Size Not Included Includes Spanner Bushing Plastic Wheel Core Material Yes Non-Marking 1 9/16 in Hub Length