You can dual-jet your brush with these nozzles. (Standard brushes are pencil-jetted) Just drill 2 holes into the brush, push the nozzles in, add some hose along with a "Y" or "T" connector and you're set.
This part can adapt your brush from a pencil spray to a fan spray.
Jam Nut used to hold 1/4in bushing to the Brakets when mounting fan jets to to a Solar or similar Brush