Back in the day (15 years ago) my windsurf board had this type of fin slot. My current wave surfing paddle board has this type of fin slot. It’s a very popular system and rightly so. It makes it extremely easy to install any fin size and shape you want and position it within the slot for a different feel. Forward for looseness, back for better tracking among other things. So, as more and more inflatable stand up paddle boards become available with the US fin box and so many already featuring it, I thought it’d be a good idea to cover how to install and remove your fin.
In the case below, we are using the Red Paddle Co inflatable 12’6″ Racing SUP. It differs slightly in that the screw head is turnable by hand and you don’t need a screwdriver. A very handy feature when you’re at the beach prepping for or packing up after a SUP session. Also that the low profile box protrudes from the board base rather than recessed within the board. Just an inflatable SUP board quirk…
Super simple, slide in and position the tab, slide in the fin, align holes, insert screw, align fin to desired position in the box and tighten screw, and you’re done. Do the reverse to remove the fin.