I tried the Brooks Large Keyhole skirt on my AT 14 and it works great! Nice taught deck but still holds tight on my 35.75" x 18.25" coaming. (Pygmy said the AT14 coaming is about 3" less wide but the same length at their standard cockpit.) The material is 3mm supratex neoprene, it has a bit more stretch and feels a little thicker than standard 3mm neo, I think it is a coarser weave and it seems to hold/suspend more water than nylon. The shockcord is adjustable, and the 3/8" width plus the extra thickness of the supratex really fills up the coaming spacer gap. The tube has cinch straps on each side, andd the Medium Brooks tube feels the same as the Snapdragon Large tube. I'm pretty happy with it, but now I have to decide if I want to get the Brooks (Boreal) or have Snapdragon custom make one. I made an outline of my coaming and will send it to Snapdragon either way.