Mikuni exploded view explained, please

[chiggy03]

Hello, on the exploded view of the mikuni carb. it refers to the throttle valve affecting throttle from 0 to 3/8, needle jet affecting from 1/8 to 5/8 throttle opening and the jet needle affecting throttle from1/4 to 3/4. Can anyone explain what these refer to - throttle valve is the pilot, needle jet the clip on the needle and jet needle being the needle itself?

Thanks, Chig

[soulsurfer]

Throttle valve is the slide (description referring to the effect of the cutaway), needle jet is what would normally be the atomiser and jet needle is the needle.
Hope this helps.