Originally Posted by
Dan Burkhart
The S3X is essentially a 5 speed wide range hub with the planetary carrier directly coupled to the hub shell, and no drive pawls on the ring gear.
The Felt Gridlock is another OEM bike with the S3X.
This reminds me of a 'hack' on Sheldon Brown's website about converting an AW 3-speed into a 2-speed fixed gear, pretty much by this method. This gives a direct drive and a reduction gear.