See the Informational videos here first. This part is a 2" Spigot X Dead End X (6) 3/4" Barbs manifold and a 2" Spigot X 2" Slip X (4) 3/4" Barbs manifold and Coupler Basic Replacement Kit. Note: 2"= 2 3/8" in PVC Plumbing. The Kit consists of the Manifold with (6) 3/4" Barbs, a Manifold with (4) 3/4" Barbs,(2) Barb Plugs, a 2" Coupler, 6' of 2" Soft Pipe. The kit is to be used to replace a broken manifold and extend the output side tubes and use the coupler to spin it to win it on the old pipe and then glue the 6" piece of 2" Flex in and then glue the manifolds in from there. The Manifold receives a 2" pipe or fitting on one side which would measure about 2 3/8" OD and then slips inside of the other manifold and then a 2" fitting glues in on the other side that would measure about 2 3/8" ID.
I had a confusing setup and Spa Guy helped me find the exact parts that I needed for the job. In particular, I need a 10 port manifold that wasn't dead end. I let Spa Guy know and he sent exactly what I needed. The parts were high quality and with his advice everything worked perfect the first time.