Teflon Needle Packing Bush
A teflon needle packing bush is a small seal through which the airbrush needle passes and is situated in the front section of an airbrush prior to the paint entry point. It forms a tight seal against the sides of the airbrush needle and prevents paint from returning, along the airbrush needle, into the trigger housing.
Teflon is highly resistant to paints and can be used with automotive paints and thinners. It will, however, become worn over time and will need replacing.
The packing bush sits in the recess of a small grub screw and is held firmly in place by the tightening of this small grub screw.