The Dimples improve the foils performance with the flat inner face allowing for more control at extreme speeds. Surfer Size: 60 - 85kg (132-187lb) Fin size. The item "3DFins 5.0 Fastlight (FCS) Medium Thruster Surfboard Fins" is in sale since Sunday, April 10, 2016.This item is in the category "Sporting Goods\Surfing\Accessories\Other". The seller is "wetfins-au" and is located in Medowie, New South Wales. This item can be shipped worldwide.