DaFiN is the most powerful and comfortable fin in the water today. DaFiN was developed in Hawaii by Andy Cochran, an Aussie who was one of Oz's early surfing pioneers. Cochran worked closely with two of Hawaii's most famous watermen, Mark Cunningham and Brian Keaulana, on the design of Dafin.Dafin delivers top performance for lifeguards and bodysurfers. It is the most popular fin with watermen around the world. Dafin was recently featured prominently in the critically acclaimed bodysurfing film 'Come Hell or High Water'. DaFin is the only swim fin endorsed by the United States Lifesaving Association, the premier professional association of beach lifeguards and open water rescuers in the United States.Dafins Weight: 1.3 – 3.0 lbs per pair (example: size ML = 2.4 lbs per pair)NOTE: If you have wide feet or are at the high end of the size chart we recommend going up a size and adding either a heel pad cinch or fliiper slippers for a better fit.Size Chart:XX-Small (M: 1-2 / W: 2-3.5)X-Small (M: 3-4 / W: 4-5.5)Small (M: 5-6 / W: 6-7.5)Medium (M: 7-8 / W: 8-9.5)Medium-Large (M: 9-10 / W: 10-11.5)Large (M: 11-12 / W: 12-13.5)X-Large (M: 13-14 / W: 14-15.5)XX-Large (M: 15-16 / W: 16-17.5)Note: Customers with extra wide feet (E and larger) benefit from sizing up.PLEASE NOTE:Dafin come out of the box with an oily silicone coating. This is to help remove them from the molds they are made in. This coating becomes white and powdery on pairs that have been on the shelf for a while. This washes off after use.Swimfins are made of natural rubber and will have imperfections/scuffs. These do NOT affect the performance or lifespan of the fins!