Here is the tiny NG 1394 filter off my Scag/Kawasaki 25hp motor. Air cooled. Runs at 3600rpm when mowing. 150 hours is roughly equivalent to 9k miles (figured at full road speed equiv of 60mph). This represents a 3 year O/FCI, just like my Dmax and Kubota. Not bad at all for an air cooled engine running under full load for 150 hours! And a tiny filter at that. Everything is as one would hope; tight, solid and no leaks or tears. http://s1333.photobucket.com/user/dnewton3/media/IMG_0133_zpsb94e72fe.jpg.html http://s1333.photobucket.com/user/dnewton3/media/IMG_0135_zpsfa2e7154.jpg.html Yet more evidence that long calendar durations mean nothing to a filter.