Heading out for a long run? Not sure about the weather, or your ability to navigate and get home before dark? When you need to bring a few extra pieces of kit with you, or if you’re going fast and light, the Dyna 6 accommodates just enough fuel and gear to get you there and back, no matter how far ‘there’ may be. With women’s specific fit for bounce-free stability and comfort and ample room for long runs requiring extra layers or gear, thoughtful and accessible storage for fuel and other small items, trekking pole storage, a Hydraulics LT 1.5L Reservoir and soft flask compatibility this pack will please novice runners and experts alike. Vest-Pack Sizing: The Dyna series comes in two sizes, XS/SM and SM/MD. Based on torso length chest circumference, these packs are sized like apparel. The surface area of the harness evenly distributes the weight of the pack on both the smaller and larger volumes.