For the environmentalists out there, the Bontrager PRO Pack Eco is a good choice for hauling your things around on the bike. It is made out of 54% recycled material by weight; Bontrager inner tubes and advertising banners. It is designed to stay firmly attached to your saddle rails with its V-loc mounting system. Two internal pockets allow you to organize your things with ease. A plus about the Bontrager PRO Pack Eco is that each bag is one-of-a-kind, due to the materials on-hand. Purchase the Bontrager PRO Pack Eco at the Trek online shop for $39.99.