what is is the nut on the pressure hose for the power steering pump. cant get it on 2003 Saturn L200

have to replace the pump but cant get the pressure line off

Asked by for the 2003 Saturn L200
Do you mean the big nut that the line screws into? You may need two wrenches there.
1 more answer
If I recall correctly it's actually 5/8" which is very close to but not 16mm.