Semi-pneumatic are an easy rolling economical solution for a variety of terrains. They feature molded-in air pockets much like the air pockets in the soles of athletic shoes to provide some cushioning during transport. ?These wheels never need air or maintenance and they won’t go flat when punctured.?Semi-pneumatic wheels offer more cushioning than solid rubber and greater durability than pneumatic wheels. Maximum load capacity is 350 pounds. For a low maintenance all terrain wheel order t oday