High Sierra AT7 Wheeled Computer Backpack 1680 Denier Ballistic Nylon Imported Main Compartment expands 2 in/5cm for additional storage capacity Recessed telescoping lightweight aluminum handle system with locking mechanism Reflective piping for added safety Height (from ground) when handle is fully extended - 42.5 Inches Features inline skate wheels that are constructed of polyurethane with ball bearings to minimize frictional resistance