Cannondale Headshock Forks

[Manitou HT]

Hello,
I recently aquired a Cannondale frame with some Pepperoni Forks, They look like the same as headshock forks. Whats the difference between headshock forks and rigid pepperoni forks? How do the internals of a headshock fork work?

 

[02gf74]

Imagine a tube over the steerer of a regular set of forks. Now imagine there are four strips of needle bearings, the steerer and tube having machined flat surfaces. The tube is fitted to the bikes head tube so the steerer and hence forks can move up and down.

Obviously there will be a spring and damper, end stops, lockout etc but basically that is it

Google wilk have diagrams and better description..