BiKASE's TriFly is an ultralight bag that mounts to your bicycle frame top tube and holds your essentials within easy reach while riding. It's great for triathlon and other events. It can also be used as an aerodynamic seat bag and fits great even with aero seatposts. This durable nylon bag is water-resistant, has see-through sides for locating what you want, a reliable zipper closure and it mounts easily and quickly with the included straps. It's compatible with frames with cables entering the top tube, too.