You want more venting? We’ve got it. The 509 Sinister X6 Fuzion Flow Goggle maximizes airflow to maintain total fog-free clarity for the most aggressive riders. Venting in both the lens and the frame optimizes airflow to eliminate fogging, while industry-first Fuzion lens technology fuses Super Anti-Fog inner and outer lenses into one optically clear view. Available HCS (High Contrast Spectrum) lens tints (sold separately) let you fine-tune your vision to fit any lighting condition.