The Enerpac CH604 is a male half coupling (usually attached to the hose) and is rated at 700 bar and has a 3/8 NPT female thread.
The Enerpac CR400 is the female half coupling (usually attached to the cylinder) and has a maximum working pressure of 700 bar and a 3/8" NPT male thread.
The Enerpac C604 is a complete coupling (male and female half) rated at 700 bar maximum working pressure and has 3/8 NPT threads.