Telescoping, retractable pull-handle convenience combined with maximum strength and durability help this line of ATA molded transit cases set a new industry standard. Molded of high density polyethylene with designed-in "roller-blade" style wheels. Molded-in bumpers defend these cases from impact damage. ATA Rated: ATA 300 Category 1. ATA (Air Transport Association) specification 300, category 1 is the highest standard for an airline transport container (a minimum of 100 common carrier trips).