The Gravelly 18 serves as three packs rolled into one: It piggybacks onto your main bag, increasing capacity by 18 liters for essential gear. Alternatively, attach it to the frame for use as a meat hauler with compression straps and an overload feature, while still having room for necessary items. When necessary, it can function as a standalone pack with stowable shoulder straps for quick stalk or glassing session.FeaturesZipper secured front pocket gives you easy access to your most important itemsCompression straps secure your load for navigating the nastiest terrainTwo water bottle pockets ensure you stay hydratedWorks with Mystery Ranch's Ultra Light MT FrameHydration reservoir compatible**These backpacks are only compatible with the 2024 ULTRA LIGHT MT frame Metcalfs. Frame sold separately.**