The Outlet Tube Assembly With Fittings attaches to the right Head. It is used on pumps older than 2013 or so. The tube is 3/8" hard black plastic. If you have a newer pump that uses a 1/2" rubber flex hose, you need the High Pressure Hydraulic Hose.
Contents:
You might not need to use the fittings but they are included in case any of the pump fittings are worn out.
If you have problems with it popping out, go to High Lifter Tech Info and click on What to Check if the Outlet Tube Pops Out
Also consider upgrading to High Pressure Hydraulic Lines. Call High Lifter at 707-923-2109 for details.