The Nathan QuickStart 2.0 6L Hydration Running Vest is a unisex, one size fits most backpack designed specifically for running. Made from lightweight woven stretch material in Vapor Grey with a lime finish, it is the perfect choice for outdoor runners. The vest includes a 6L hydration system, making it ideal for long runs while keeping you hydrated. The QuickStart 2.0 model by Nathan is known for its lightweight design and convenient features, making it the perfect companion for avid runners looking for a reliable hydration solution during their workouts.