Avenir Excursion Rack-Top Bag (830 Cubic Inches) with Mini Tool Box (fs) Rack-top bag made of tough 600-denier polyester Easy Velcro mounting system attaches to rear bike rack Fully insulated main compartment for cool drinks or food 420-denier ripstop nylon outer pockets; reflective piping Rear light clip for safety; 830 cubic inches of storage