Polyurethane tread with plastic core stepped face wheel. Size: 5" diameter, 1-1/4"(1.25") width, 5/16"(0.312")Axle bore, hub 1-5/8"(1.625"). Dual precision ball bearing and quiet operation, more heavier load capacity than other marketing products: Total up to 1400lbs. Lowest Highest Temperature:-40F to +180F,resistant oil, acids, grease and water Non-marking and floor protective. Fits most of shopping cart, grocery carts, moving dollies, office &store fixture, hotel and food equipments. Life time waranty: 90days free return.