This is the heart of the Scolster. This “wing” is what allows the holster to be stable and still conform to your body.
You can simply swap out your mag side and clip on your Echelon or Echelon Prime with this piece to turn it into a gun side only holster, AKA a Scolster.
Buy this with your Echelon or Echelon Prime to get both styles of holsters.