This is a Pentair 2 in. PVC Slide Valve with a unique handle design that makes it easier to operate. It is also known as a Push Pull Valve because you pull the handle to operate the valve, and push it back in to shut the slide valve off. Due to it's design, it has minimal flow restriction. Inside it has highly lubricated disks on it's shaft to make sliding the shaft much easier to use. It includes 2" PVC unions to connect the valve to the corresponding sand or D.E. filter. Check out our video on YouTube for a visual demonstration. For more information, contact the pros at PoguePoolSpa.com.