MaxFlow Filters are the ONLY aftermarket filters that are 100% USFS approved. Don't risk being shut down on Forest Service property.  Reference the (MSE) SAG HS type A. 

MaxFlow® air filters trap the smallest particles while flowing full CFM for up to 30 times as long as stock air filters.  This helps your saw breath better during prolonged use in adverse conditions, resulting in smoother running and more power.  Unlike pleated filters, MaxFlow filter elements are washable and re-usable so they last longer and cost less.  Foam elements do require the use of foam filter oil (sold separately).

For more than 30 years MaxFlow® filters have featured ONE PIECE foam elements with no glued seams to fall apart.  No seams mean longer lasting elements with no chance for dirt to penetrate.  Don't be mislead by glued foam where gas and vibration causes the glue to fail.

Replacement of the air filter on Non-HD filter equipped with  Fleece, Flocked or Screened Air Filters will require installation of the  Stihl HD backing plate and other parts (not included).