The Circuit™ Vest puts you in control of your body, so you can focus on self-discovery and personal bests. Crux® reservoir keeps things flowing, and the trekking pole attachment helps keep you steady on your path.While our women's specific design ensures that every mile is comfortable. This vest is the perfect companion to your weekend adventures. It's lightweight, stretchy, and breathable so you can focus on what really matters: running and getting lost in the woods.