Not sure exactly how long I had this thing in the car (maybe only a couple of weeks, I changed back to conventional filters after I stopped using the Nissan for auto-x), but when I pulled it out of the box, I was surprised to find it still looked clean. In either case, I’m selling the filter along with the cleaning kit together. Part number 33-2031-2 on the filter, here is what it fits:
http://www.knfilters.com/search/applications.aspx?Prod=33-2031-2
Recharger kit is 99-5000.
$57 value, yours for $20.