MGB: Clutch PP bolts

Anyone know the bolt size off hand?

I might if I could just figure out what PP means.
I'm trying but I cant think of any bolts directly involved w/the clutch.
Pedal?
Pivot?
Other?
I'll probably regret this.
RS

Robert - Pressure Plate perhaps?

5/16 fine (24tpi) by 7/8 length

Can't swear that what I have is original but they are what I could lay my hands on (screwed into a late model flywheel), and strike me as right. Head marked with three lines (denoting grade) and GSF and S

Only doubt I have is I thought the originals had a little unthreaded shoulder on them, but it has been a long time since I have changed one out.

[quote=PaulP]
Robert - Pressure Plate perhaps?[/quote]
DUH! thanks for the sensory input.
RS