We tried doing that and the filters are so thn that we didn't trust them a 3rd or 4th time. I always check the inside of the airboot when I change filters and have never found grit when using them the 1st time but after a cleaning or 2 have occasionally found a small amount (any is way to much). With the Notoils or twinairs Cleaned and oiled I have never found anything inside the boot.YZ-212 said:The ready filters are just that a regular pre-oiled filter. Once it's dirty just clean it and re-use like any other filter. At leat the one i get are reusable. I also use the notoil and love it.