Choose your weapon. The Futures Fins Performance Single Fin offers a solution for every set up. The 4.5" is the standard thruster center fin, with a 1-Shot Box base. The 6", 7" and 8" are different size 2 + 1 center fins sized at 1" increments, to allow for customizing your set up. The 9" is the single fin version, providing enough fin area for that traditional longboard feel Fin Size Detail table { border-collapse: collapse; } thead th{ background: #F3F4F6; color: #252627; padding: 8px; border-right: 1px solid #555; border-bottom: 1px solid #555; border-left: 0; } thead th:last-child { border-right: none; } td{ padding: 8px; border-right: 1px solid #555; border-bottom: 1px solid #555; border-left: 0; } tbody tr:last-child td { border-bottom: none; } tbody td:last-child { border-right: none; } /* bottom-right cell: guaranteed */ tbody tr:last-child td:last-child { border-right: none; border-bottom: none; } Size/Height Base Area Foil 4.6" 4.5" 15.30"² Symmetrical 6.0" 4.6" 20.00"² Symmetrical 7.0" 4.8" 24.50"² Symmetrical 8.0" 5.60" 31.50"² Symmetrical 9.0" 6.30" 39.80"² Symmetrical