Fin Box System Selection Guide
FCS II (FCS 2) fin system is the latest innovation from Surf Hardware International and features a screwless click-in fin mounting mechanism. This fin box is very strong and installed right into the foam shape before laminating. When sanding the sealcoat the fin box channels will be exposed to allow a fin to press in. Installing the FCS II fin system requires a router, FCS II install kit, and FCS II install dummy fins. The FCSII fin boxes are sold in pairs in a few cant degrees - 0 degree, 3 degree, 5 degree, and 9 degree. See our Surfboard Design Guide for more info on surfboard fin cant and how if affects the performance of the surfboard. The FCSII fin boxes are designed for FCS II screwless fins but also can be used with FCS dual tab fins with special fin adapter. The FCS 2 Fin System is our preferred fin box at Greenlight for it's ease of installation and high strength. We use them in all our personal boards and never had a problem.
FCS Fusion is another strong and easy to install pre-lamination fin box, just like the FCS IIs but for FCS twin tab fins with screws. This fin box is a slightly different shape and is to be installed with the FCS Fusion Install Kit, router, and install dummy fins
Futures Style fin boxes are made for futures single tab fins and are another fin system that is installed in the foam shape before fiberglassing the bottom of the board. Installing the futures style fin boxes requires a router, futures style fin box install kit, futures install dummy fins, and 3/8" wide fin box install tape. Futures style fin boxes come in 3/4" depth for front side fins and 1/2" depth for rear center fins and rear quad fin sets.
The most affordable fin box system to install into a surfboard is FCS X-2 or FACTORY fin plugs. They are installed after you sealcoat your board, before sanding. All you need is a power drill, install drill bit, Quickset jigs, and install dummy fins. Use the X-2 or FACTORY plugs with FCS twin tab fins. Great fin system for beginners but not the strongest...
Note: Due to this plug design and amount of resin needed to install them, when installing these plugs in EPS foam use SLOW Hardener Epoxy or install with 2 separate pours of FAST Hardener Epoxy to reduce the risk of melting the foam (epoxy exotherm)
Center fin channel boxes come in two lengths, 10.5" and 8.5" and are installed into longboards, stand up paddle boards, and single fin surfboards to accept a center fin with screw and plate to lock the fin in position. They are installed with a center fin install kit and router. Center fin channel boxes allow the fin to slide back and forth to dial in the turning performance of the surfboard or stand up paddle board. These center fin boxes are also used in foil boards to attach the foil mast to the surfboard.
Glass-on fins are old school style and provide great dynamic response as they are connected directly to the surfboard with fiberglass. Glass-on fins are glassed on after the lamination and before the sealcoat with fin roving and multiple layers of fiberglass running up each side of the fin to make them part of the board.