Return Valve is built out of brass with a viton seal and a 1/4" compression fitting. This check valve is designed to keep a positive pressure on the system for immediate starts and quick shut offs. This is factory pre-set and needs no adjustment.
We use Shoo-Fly for all of our insect problems. They have been a stellar company to work with and produce an exemplary product that provides almost 100% eradication of flying pests.
Melanie and JT Burnley - Wrenwood Dressage