Bought this with the PSE 1800 as a replacement system for another brand's 4 year old system.  The plumbing were already in place and this kit made it flexible and easy to connect, saved me a lot of time not having to measure and buy parts for the manifold.  I did have to buy a Sharkbit 90 degree angle to connect the supply line to the new pre filter as it stuck out more from the wall.  I had to turn the tanks around as the water source was coming from the right side of the system.  No biggie, the flexible metal hose made it very easy.