DaveG's Airbrush Exploration - Richpen 212B, with needle and nozzle cap removed. Same basic construction as found on the Micron brush, with air within the head and over the nozzle being utilized
Lenz Arts - Art Materials -> Richpen Airbrushes -> Apollo Parts
RICHPEN REPLACEMENT PARTS
Richpen 033g - Nozzle | Hobbyland
Mike Learn's RichPen Airbrushes
Richpen Phoenix and Gemini airbrushes | Airbrush Forum