Adler Airforce 9001 Airbrush is some kind of knock off of H&S airbrushes. Unfortunatly there is no spare parts avalible for it. I try to fit H&S parts and it turn out that with original PTFE nozzle seal there is air leak. So I cut about 1.5mm in lenght PTFE tube and put it on a H&S nozzle as new seal. It worked.