Hi Elliot, there are so many coamings and skirts that the sure thing is to put the skirt on the boat before buying,, , so one manufacturers "nylon sea kayak sprayskirt with adjustable waist" maybe slightly different than another manufactureres "nylon sea kayak sprayskirt for keyhole cockpit with adjustable waist". With that I've found most $50 nylon skirts will fit up to 20"x35" exterior dimension coamings. Unfortunately most inexpensive nylon skirts aren't very good at keeping out the water should you intend to learn how to roll. Aquaterras adjustable neoprene skirt for $85 is close to one size fits all, maximizing the budget I'd shop around for seconds at shops or online.