Water-resistant TPE coated polyester ripstop & 600D nailhead dobby polyester 30 litres Insulated cooler section Includes rain coverThe ultimate backpack for school, work or travel... the Overtime Hydro features three distinctive sections. Combined with a padded laptop section, handy insulated cooler pocket ideal for lunch, external drink pockets and Tough Base protection. At 33 liters this pack is large enough to fit everything you need, and then some. Made with a water resistant TPE coated polyester ripstop, this bag also includes a hidden rain cover to ensure your belongings won't get wet when it starts raining.