400 Quad Rear Height: 4.00 in - 10.2 cm Base: 3.89 in - 9.9 cm Area: 12.41 in² - 80.06 cm² Foil: Symmetrical Tang: 1/2" & 3/4" tangs The largest symmetrically foiled rear fin, the 400 rear is perfect for the heavier surfer for an increase in drive and hold through turns. Available Materials: RTM This fin set up is only for the rear fin setups. Recommended Front Fins: VII QFJC1 Note: Quads have either 1/2" or 3/4" depth. If the rear boxes are shallower than the fronts and are marked with an "X" then they are 1/2". If the front and rear boxes have the same depth and are marked with an "F" then they are 3/4". You will need to know this during checkout when you purchase these rear quads.