The performance program offers a solution for every setup. The 4.5 is the standard center fin of the Thruster with a 1-shot box base. The 6, 7 and 8 inch fins are different sized 2+1 center fins that are sized in 1 inch increments to allow customization of your setup. The 9 inch fin is the single fin version and offers enough fin surface for traditional longboarding.
