Naked Viking Surf: Kestrel Quad Fins (Single Tab) The front fins are an adaptation the Marlin twin template. The idea was to split the surface area of the twins into a quad setup for a looser, more playful feel. NVS drew in the trailing edge for the quad fronts and scaled them down some. The trailers complement this outline but are considerably smaller; providing stability without sacrificing flow. DETAILS: Front Base: 5.93 inch Height: 4.84 inch Area: 22.38 sq inch Foil: Flat SeriesIII Trailers Base: 3.29 inch Height: 3.15 inch Area: 9.85 sq inch Foil: Flat SeriesIII