The Belt Wing Tuckable Holster for the FN 509 Compact/Midsize/Tactical 3.7''- 4.32'' offers a discreet way to appendix carry your gun. It is compatible with virtually any red-dot sight on the market and the open-muzzle design allows threaded barrels to pass. The protruded area on the trigger pushes against the backside of the user's belt in order to reduce printing.