Bulky backpacks are out Chest Packs are in. See for yourself how the RAVERUNNER Chest Hydration Pack is the #! selling winter hydropack. • Freeze-Resistant Hydration 🥶 • 17oZ soft flask included 🥤 • Fits UNDER or OVER your ski jacket🧥 • Multiple pockets to carry the essentials⚙️ • Easily Accessible phone pocket📱 • Back Panel pocket for added Hydration💦