CamelBak Outlaw Scorpion Hydration Pack (2L). I used this for long-distance running, cycling, and day hiking. I liked the design, but I'm selling it because I bought something else and haven't used it much. In addition to the 2L hydration reservoir, there are pockets that can hold a cell phone, wallet, towel, and T-shirt. Also, the hydration hose can be stored on the shoulder strap, so it doesn't get in the way. After use, I washed it with a special sponge and brush, so there is no dirt inside the pack or hose, but the pack has lost its luster due to aging.