FCS II Matt Biolos Split Keel Quad Fins

Matt 'Mayhem' Biolos's 'MB' shaper fin. High area specialty quad set adds bite and control.

Upright keel template designed for traditional fish shapes.

Rated 5.0 out of 5
Based on 3 reviews
Product In Stock


  • Overview

    • Matt 'Mayhem' Biolos's specialty quad fin set.
    • High area quad keel set adds bite and control to hybrid boards with wide tails, without sacrificing pivoting capabilities.

    Board Types

    • Designed to fit the FCS II Fin System.
    • Recommended for all board types including modern fish and hybrid models with moderate-to-low rocker.

  • Performance Glass

    Performance Glass (PG) fins are machine cut from layers of solid fiberglass. These fins are stiff, and are widely used by pro level surfers because the integrity of the flex is maintained under immense force, and in the most extreme of conditions and situations.


  • X-SMALL (Under 55Kg / 120 Lbs)
    SMALL (55Kg - 70Kg / 120 - 155 Lbs)
    MEDIUM (65Kg - 80Kg / 145 - 175 Lbs)
    LARGE (75Kg - 90Kg / 165 - 200 Lbs)
    X-LARGE (Over 85Kg / 190 Lbs)

    View the FCS Fin Data page for Base/Depth/Area/Foil information.



    average rating 5.0 out of 5
    Based on 3 reviews
    • 5 Stars
      3 Reviews
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      0 Reviews
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      0 Reviews
    • 2 Stars
      0 Reviews
    • 1 Star
      0 Reviews
    100% of reviewers would recommend this product to a friend
    3 Reviews
    Reviewed by Jim B.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5
    Review posted

    Quad Fins for Fish

    Compliments the ...Lost Hydra well. Lot's of drive in smaller weaker surf.

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    Reviewed by Shahaf H.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5
    Review posted

    Best Fins!!!

    I have the Lib Tech Hydra 5'3" and it works perfectly!

    Very responsive, generate speed and the control is absolutely amazing!

    Highly recommended to have in your arsenal!!!

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    Reviewed by Tony, from Australia
    Verified Buyer
    I recommend this product
    Surfing Ability
    Intermediate
    Board Type
    • Funboard
    Rated 5 out of 5
    Review posted

    Great fins

    Great looking Fins thst are excellent for hold on steeper waves and provide heaps of thrust amd work great on the Lost RNF Retro and any similar style board.

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