In order you put them:
Down Slow
Up Fast
Fast Line
Up Main
UNF can depend on the area, for an EMT service around Nottingham it will mean Up Nottingham Fast
D can also depend on the area, for an EMT service around Nottingham it will mean Line D
UN can also depend on the area, for an EMT service around Nottingham it will mean Up Nottingham, or Up Newark.