The Gaer® threaded ball check valve is an indispensable element and widely used in pipes for wastewater, dirty water or water with a high concentration of suspended solids. Obviously it is also suited for drinking water pressurized pipelines. Its design guarantees very low load losses thanks to the total passage of the fluid and an impossibility of obstruction. It is a completely watertight and maintenance-free valve; its assembly depends on the direction of flow.