This slim hydration bag is perfect for the mountain biker looking to spend a few hours on the trail. The Drafter can hold enough hydration for three hours. Its slim design allows for very little wind resistance. The Drafter has an insulated compartment for a hydration reservoir, elevated airflow back panel platforms and interior mesh tool pockets for your gear. If you are looking for a bag that can take as much of a beating as your bike can, then don't look any further!