What does the top control knob do? This is a Binks M1-g spray gun. The bottom knob controls fluid but the top knob doesn't seem to make a difference on anything. I
Binks Bbr Spray Guns X 2 | eBay
Low-Volume Binks Diaphragm Pumps - Professional BoatBuilder Magazine
Binks AA4400M Air-Assisted Airless Spray Gun - Elmbridge UK
Binks 10 Litre Zinc Plated Pressure Pot Package 2 from SprayDirect.co.uk
HVLP Spray Gun Catalog - Midway Industrial Supply
BINKS TROPHY MANUAL SPRAY GUN - Fluid Transfer Systems