Ever wonder why some nailers seem to hold up and last longer than others? One major reason is that some guns (like Max) have a built-in air filter that keeps sand, grit, rust and pipe scale from destroying moving parts inside the gun. I repair a lot of guns and when I open up a Max gun the inside is generally dirt-free and pristine, but when I open up other brands generally the head valve (the heart of the gun) and head cap have deep scratches (Grooves due to sand and grit making the repair time and parts cost far greater. All it takes is a bit of sand coming from hoses dragged in the dirt to cause a new roofing nailer to fail, sometimes in only a few weeks, so I decided to look into an after-market filter that was feasible to use. This filter has a small flexible whip hose and screws into the gun where the nipple goes so it stays with the gun when disconnected creating a sealed environment. The whip hose is flexible so if the gun is dropped or impacted it won't break your air inlet cap. The filter is self-cleaning - every time you disconnect the gun the pressure inside blows only dirt retained in the filter right back out. This outstanding filter will keep down repair costs and gun downtime. Note: The filters are custom made to fit any gun configuration. * Only $35 with the purchase of any of the rebuilt nailers I have for sale* ** ~Now made with super tough and flexible GREEN LINE Air Brake Hose Call Sheldon at 236-464-5990