Marathon 6x1.50" Semi-Pneumatic Tire on Wheel 6x1.50" Tire. 6" Tire Diameter. 1.50" Tire Width. Semi-Pneumatic Tire made of rubber. Diamond Tread. No flats! 1.375" Offset Hub. 1/2" Ball Bearings. Multi-purpose replacement tire. 40 lb load capacity. Not for highway use.