These Flying Diamonds Kai Sallas HP Sides Fins are super-fast and full of drive. Their balanced foil generates lots of lift for accelerating speed in turns without creating excess drag when going down the line. They match up perfectly with Kai's HP center fin as well as any proper HiPro center fin in the market. Go with Smaller sides when paired with longer centers and Smaller conditions/surfers. Run with bigger sides when going with Smaller center fins or looking for more drive off the rail in larger waves/surfers.