The Slip over hook head adapter is made so you can use any of our standard hook heads and a 10' piece of 1 1/4" of non threaded EMT. EMT metal pipe is found in the electrical department of your local hardware store and looks like silver fence post. The slip over hook head adapter slides over the EMT, then the hook head screws on to the top. This is much cheaper than having to buy the threaded 1 1/4" black gas pipe. Although in most cases we recommend the black gas pipe when going up to 20'.
This does not include hook head.
What you are getting is two pieces below. The first is a fitting that screws into the hook head and one 14" piece of pvc pipe that slides in to the threaded fitting. The 14" x 1-1/2" piece of pvc has a 1-1/2" ID.
Please look at detail images below.