600D Polyester with water resistant coating,Reinforced stitching, oversized gusset, rubberized bottom, and heavy coiled zippers. ,Featuring Integrating PALS (pouch attachment ladder system) for MOLLE pouches (modular lightweight load-carrying equipment) ,Padded back panel, top handle, adjustable unisex sternum strap, ergonomic shoulder straps with 2-way adjustments.,Two internal mesh pockets, second compartment has three slash pockets, front pocket organizer, internal carabiner, and D-ring attachment,12 channel PALS webbing system,Bottom straps and 4 compression straps.,Hidden zippered back compartment. ,Note: this pack is H2O hydration compatible.