These items are HDPE (High-Density Polyethylene) compression ball valves used for water supply and irrigation systems.Function: They act as flow control devices, allowing you to turn the water on or off with a quarter-turn handle.Installation: These are "twist-and-go" fittings, meaning they connect to HDPE pipes without needing specialized welding tools or solvent cement.Versatility: They often feature a double union design, which makes it easy to install, remove, or maintain the valve without cutting the pipe.