Alpinestars Orbit Back Pack 420D Nylon / 420D Ripstop Nylon / 1050D Ballistic Nylon / Hypalon Reinforcement Fully expendable from 28L to 35L (approximately) 4 external pockets (2on the upper front / 2 on the sides) + 1 PU Mesh pocket on the front + 1 main waterproof compartment (wrapping closure) Retractable shock cord on the front Internal removable organizer featuring 15in. laptop and 11in. tablet protective sleeves Separated Water bladder pocket and full hose routing system on the left or right side