Flash or PCV either one will work for you. Or you can just put the regular filter back in and plug you 02's back up. I have been running mine with just gutted pipes for over a year with no problems.
2011 Cross Roads Sunset Red
OEM short windshield, passenger backrest, crash bars, saddle bag bars, heated grips, vinyl closeouts, tachometer, ambient temp, LED headlight, luggage rack. WD lay down licence plate.