A HOME RUN!!! I now have about 90 hrs on my RZR since the install. I live in upstate S.C. where the dust is as fine as baby powder. I had dust in my intake at around ten hours. I tried different filters, sealing off any gaps etc. Nothing worked. I have check it many times since the install of the waterproof box and its STILL clean. Plus the extra HP was a nice surprise as well. GREAT PRODUCT!! Should be purchase by EVERY RZR owner. First a helmet then a BTI filter box!! From: Andy L, SC