The Small Check Valve is built out of brass with a viton seal and is designed to keep a positive pressure on the system for immediate starts and quick shut offs.
The Large Check Valve is also built out of brass with a viton seal. This check valve allows fluid to be pumped from the drum into the system freely and then restricts the flow of the liquid back to the drum. This prevents the pump from losing it’s prime and having dry starts.
Shoo-fly’s Aluminum Filter is designed and built with the highest quality aluminum available. There is not a better filter available on the market. Clean the filter each time the drum is refilled with insecticide.