I got my Waterway on eBay, and it tells you how to size it in the information section. It says to get a size bigger than you think you are because they come really tight. I'm a size 8 (American), and I have a 240, but I probably should have gotten a 260. http://www.ebay.com/itm/MONOFIN-FOR-...ht_1207wt_1141