Center pinning is another form of fishing that allows the angler to present an almost perfect or drag-free presentation to the fish.  Using an ultra-light rod in lengths from 11' to 15', reels with ultra-smooth bearings and no-drags and a floating monofilament, the angler casts a float and a series of split shot placed along the leader to the fly/bait into the water.  From there, the current takes the fly and presents it to the fish in the most natural way possible.

Below you will find several links explaining the rigging, tackle used and different methods to cast the the entire rig. 
Casting the Center Pin Rod
Rigging the Float
Selecting the Right Float
Line Selection
Split-Shot Patterns
Information contained in the links above courtesy of Anglers International.
Sample Pin Rod with sliding rings and a split handle...
 
Center Pin Basics
K Kustom Rods