I believe the Tout Terrain Ergo Stop is a specific fitment for their branded bicycles, which have lands (blocks) brazed to the tops of their head tubes, one each side. A bracket clamps to the steerer and extends downward to hit these lands and so limit the arc of the fork, sparing a headlight from crashing into the downtube while parked. (Thorn/SJS Cycles makes a clamp-on version for recent models with an extended head tube. Like the original TT fitting, it only prevents light damage and doesn't hold the fork stationary while parked).
If you look closely, the lower stainless plate of the TT Ergo Stop sits between the headset and end of the top tube and is folded over these lands at the front to prevent the baseplate from turning while the stopper is engaged. This is what makes it specific to Tout Terrain bikes.
Best,
Dan.