Legacy Pro Backpack Gray Flannel. For over 30 years, our goal at FUEL has been, and continues to be, to provide timeless, innovative, and durable products to our loyal customers that stand the test of time. Our Fuel Legacy Collection does just that! By combining durability, high quality standard, and classic design physiques, along with superior fashionable accents, our backpacks with their thick foam ergonomic padded backs and high capacity offer much more than our competitors. Better yet, all our items are backed by our limited lifetime guarantee, so your worry-free adventuring can continue without a trace of hesitation.