【Solid】Our tire set is designed into a solid construction that you don’t need to worry about puncture or deflation of the tire. The solid tire can save you from undesirable and frequently pumping up, which is durable for long-time service and can save you from much trouble. 【Heavy-duty】This sack truck tire set adopts heavy-duty ball-bearing, grease fitting and 16 mm (0.6’’) axle bore. 【Well-adapted】This sack truck wheel can adapt to various ground situations, such as sand, mud, lawn & garden. 【Excellent Bearing Performance】Our sack truck wheel features excellent strength, boasting a maximum weight capacity of 250kg/550lb for four wheels, 100kg/220lb for two, and 50kg/110lb for one.