Unions & Fittings may seem pretty mundane, but they're necessary for a well-running filter system. Most people really don't want to know about the "nitty-gritty" of their pools- they just want to look outside and see a beautiful blue body of water waiting for them to take a dip and relax. But to know how it all works, then you need some information on these items. Here's a list of the most common unions and fittings:

Union Used to disassemble your pump and filter easier and quicker.	3-Way Valve Diverts water from one direction to another by turning the handle.
90° Elbow Try making a turn with rigid pipe! This little fella makes it easier.	45° Elbow The kid sister to the 90° Elbow, but this one is only half as bent.
Coupling When you need to connect sections of piping, a coupling joins two pieces seamlessly.	Check Valve Prevents water from flowing backward helping to keep the pump full of water.
Return Fitting Returns water to the pool after its cleaned by the filter. They can be screw-ins or glue-ins and come in a variety of sizes.	Brass Gate Valve Still in use today, but not as popular as they were years ago. Used to open and close off the flow of water.