1.flat free 2.longer service life 3.high load capacity 4. ... flow rate3. polyurethane tires with the benefit of never going flat 4.Many types and varieties, it's also economy and ... the customersWe promise to supply you with high quality solid wheels,and aslo OEM service for different colors PU Foam Wheel ... '',13'',14'',15'',16'',18'',20'',24'',26'' pu foam wheels 12x3.50-5 for hand truck