SHANGRI-LA Large Outdoor Pack Tactical Military Assault Backpack & 3 Day Pack MOLLE for Heavy Duty Compatible for Hydration System Tactical backpack made of 600D strong nylon & heavy duty big teeth zippers. US Army style backpack has a HUGE capacity plus a ton of MOLLE webbing for all your gear requirments - easy as a 3 day outdoor bag 3 MOLLE BAGS INCLUDED - With a detachable bug out bag that can be used as a waist, fanny or shoulder pack & removable side packs, you get triple the options to configure for your mission MOLLE external expansion system designed to be used in combination with other equipment, you can load pockets, water bottle bag, accessory kits and other. Specialized compatible with Hydration System