Our Pooch Pack is constructed of heavy-duty, lightweight, water resistant nylon material. Features include 2" nylon straps, our exclusive breathable mesh top to prevent overheating and a fully adjustable neck strap with a snap hook for easy removal, and made from elastic to ensure a proper fit. Both cargo packs have a "quiet" zipper for easy and quick access. Two adjustable nylon straps on the bottom help keep the pack firmly fitted and in place. Large Pooch Pack fits dogs from 50 to 90 lbs, and the small fits dogs from 25 to 50 lbs. Pooch Packs are available in solid colors.