Captain Fin: Jeff McCallum Quad Black Fins (Twin Tab) Master surfboard craftsman Jeff McCalllum designed the McCallum Quad. This is a medium sized fin built for speed. All four fins are the same size and have a flat inside foil generating maximum drive down the line. Great for your retro fishes and wide squash tail boards. This set comes with FCS II Screws. DETAILS: Template: Drive—perfect for a speed burst and control on wider tails. Size: Recommended for medium size surfers 140 lbs. to 195 lbs. (63 kg. to 88 kg.) Construction: Honeycomb Construction Flex: Medium Fin Specification Front Fins Rear Fins Area 12.38 12.38 Height 4.125 4.125 Base 3.75 3.75 Foil Flat Flat