Stand up paddle board fins
Fins provide stability and traction to your board when maneuvering through water. It's fundamental that every stand up paddleboard have at least one large single fin placed in the middle, center fin box. This center fin helps with directional paddling, ensuring you move in a relatively straight line toward where you are paddling. Without any fin your board would slip and slide around on the water and it would be tough to move in a desired direction without zig-zagging.
Adding two side fins, commonly known as a 2+1 set up, to your SUP will dramatically help your boards traction as well. When surfing this is highly recommended in order to always have at least one fin in the water at all times, even when your board is turning and on its rail.
Tower SUP fins
This is the tool-free model (with the black screw top) that has an integrated screw attached to the fin base. You can turn the screw knob with your hands. It can also be done with a large screwdriver, but you can use your hands in a pinch. This method provides a secure hold onto the board and if installed properly will guarantee your fin will not come loose while in use.