The QD2 4” Thermotech is a medium sized quad rear with a symmetrical foil. Made in Huntington Beach, the Thermotech product line does not have the traditional plastic feel of a composite fin. Instead, they have a consistent flex that creates drive and release through turns. This pair of Quad Rears can be combined with any Futures front fins to suit your riding preference, board design and waves. They will favor boards that have the rear boxes set off the rail, closer to the stringer.