The Ultragard? luggage rack bag is made with high quality weather resistant materials, durable construction, and a sturdy mounting system. A large main compartment allows for maximum storage, overall size 20" x 10" x 8?". Four additional easy access zippered compartments, and two expandable side pockets add up to 3,320 cubic inches of extra storage space on your bike. Also included are a rain cover and a comfortable shoulder strap.