We The People Holsters IWB Holster for Echelon 4.0C Red Dot Cut

We The People Holsters lists this shell for the Echelon 4.0C with a red dot optic cut, carried inside the waistband on the right side.

The fit is called out down to the 4.0C designation, so check the marking on the gun rather than going by the family name alone. The optic cut is the other thing to confirm against your pistol: it is what lets a slide mounted sight clear the mouth of the holster on the way in.