Hello there, hope everyone is well. I am waiting on a GRS GraverMax G8 and just discovered the oil-free air requirement. I have a 20 gallon Campbell Hausfeld compressor that of course has oil. Certainly this problem has been addressed before by you fine gentleman and I just want to be absolutely sure to get an adequate filter to ensure no harm comes to my new long awaited toy. If anyone knows of a proven brand or what to avoid any recommendations are appreciated. Thanks for your time.