"Available in two lengths:
65mm (2 1/2 in) for top-mounting or 72mm (2 7/8 in) for under-panel mounting."
That refers to how you mount the stick itself.
You can rout into the top of the CP, to mount it from above, or use the longer handles, and mount from below.
I routed the bottom of my 3/4" CP to get just a little more height out of the long balltops.
The short balltops barely clear the CP when bottom mounted without routing.
The long balltops felt short to me without routing the bottom.
With the bottom routed about 1/4-3/8", the long balltops feel about right to me.
They are still shorter than my Wicos, but I'm not skinning my knuckles on the CP.