Can be transformed from a backpack to a trolley with smooth, quiet wheels and telescopic handle. For notebooks up to 39.6 cm (15.6") Environmentally friendly notebook backpack made of recycled water bottles Use the zipper to expand the man compartment from 35 to 40 litres Grab handles on the top and side, plus ergonomic shoulder straps and a padded, mesh back for that ultra-comfortable carry.