All HUDSON Fins are hard anodized aluminium for maximum durability and corrosion resistance.
The Four/Quad Fin is offered in both Breakaway and Classic style.
The Breakaway style was introduced in mid 2005 to allow for a quick onsite replacement option, and can be used on any HUDSON Four/Quad with a set screw at the bow end of the fin box.
There is an installation guide - click here.