I have some old 4" redhead self-locking storz couplings and wanting to re-use them on new 4" nitrile rubber fire hose. I am needing to know if they are universal or not before I purchase new hose for the old couplings?
Are you asking if the old 4" redhead storz couplings are universal? I am not familiar with that line but take the coupling and try it with other brands. I suspect they are....
We buy new hose and recouple it with old couplings all the time. You need to pressure test the end product to assure your work is NFPA compliant.