King fins are hand-crafted from composite materials, developed for slalom windsurfing. Since 2012, we have been constantly improving the shape of fins with the goal to make them fast in any conditions. Today, we offer autoclave quality and ready-to race fins that you can sail with confidence.

Current model is a fifth evolution, designated as E5; in this model we modified the leading curve to obtain smaller area of tip to increase  top  speed.

In each fin, there is up to 38 different plies from 6 types of fabrics, cut to lengths to achieve standard stiffness. We recommend standard middle stiffness (M) for all-around performance but we can also make much softer (S or S-) and harder (H) variations upon request. Rake angles are set to 3.5° for 48-50 cm, 4° for 42-47 cm fins and 4.5° for tuttle box fins from trailing edge vertical. 


The autoclave technology for composites is primarily used in aerospace, marine industry, for high performance parts in Formula 1, racing cars, etc. The autoclave is a heated pressure vessel which provides a high pressure for compactions of laminates. This results in quality composite parts with highest possible fiber volume content and near-zero porosity.

King fins are made from epoxy/carbon/glass fibers in two-part molds. We are using autoclave with programed pressure-temperature-time cycles. Our advantage is that with autoclave, we can reproduce fins with no variability- two fins feeling exactly the same in the water. 

King fins autoclave


We put a lot of effort to deliver perfect, defect free surfaces. The surface, trailing and leading edge is grinded up to 1200 grit SiC grinders. This treatment gives smooth surface for laminar flow. Clean and degreased fin’s surface is important for optimal performance without spin-outs. Each fin is inspected for quality before being shipped-out to customers. Boxes are finely adapted to tuttle and deep tuttle boxes for most boards. Since 2022, we produce serial 100 % prepreg carbon boxes.



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