1200-denier Technolast water-resistant, UV-treated polyester construction. Main compartment features clear plastic panel to allow manipulation of an MP3 player (retains enough sensitivity to use with gloves on). Smaller rear compartment also features clear plastic panel to allow viewing of cell phone, etc.. Mounts with rare earth magnets. Clear rain cover. Measures 13″ L x 6″ H x 10″ W.