i bought a Volant CAI last year i think it was. My powercore filter that came with it would get wet sometimes when raining and also it became really dirty and i tried "blowing it out".... I checked it this past weekend and it was dirty. I loosen the clamp and go to take the filter out and the rubber around it comes completely off. I contacted Volant a while back to replace the filter with a Pro5 filter. Their responce was "the CAI for the Nitro 3.7L has been discontinued" So i thought "no sh^t" and replied back asking for a part number to replace the filter i have with a Pro5 filter.... No responce! So i bought a K&N and i'm all good now Part # RU-3100 fits perfect!