The Stinger 22L is an incredibly versatile welded-seam roll-top drybag designed to be mounted as a tail/fender bag on smaller bikes, or as a topper on hard-sided panniers and/or top boxes. It also turns into a backpack, in case you need a daypack for hiking into a hot spring, or making a quick trip to town for supplies. The backpack straps stash away in a flat external pocket, and clip to two d-rings on the bottom of the bag.