Solas DynaFly ys-df-15/22 Waverunner impeller will give increased acceleration and top speed. R Great for pulling skiers and Racing... Great for Stage 1 kits. Pitched for Pro performance R.  Fits Impeller Yamaha FZR, FZS 08-13, FX Sho 08-up, FX Cruiser SHO 08-up