Camelbak VeloBak Women's 72 Oz Wearable Hydration, Medium, White/Silver The first 3 pocket jersey designed with integreated hydration Vest design offers maximum mobility and comfort under any jersey. Pouch holds a CamelBak 72 Oz. reservoir firmly on your back Chafe-Free flat seam stitching eliminates abrasion along seams Air Mesh insulated back panel insert keeps your back cool and comfortable while insulating the water in your reservoir Quickwick fabric keeps you dry and comfortable.