The 6354DO features the Automatic Locking System (ALS) and is specifically made for use with red dot optic-equipped weapons.
Tactical 6354DO Holster Drop Adapter Quick Release Glock Holster Leg Belt Compatible G17 G19 With X300/X300U Weapon Light - AliExpress
SAFARILAND 6354DO ALS OPTIC TACTICAL HOLSTER - SDTAC
Tactical 6354DO Nylon Wrapped Holster Automatic Locking System 3 holed G17 G19 Glock Pistol With X300 X300U Light Red Dot Optic
Safariland ALS holsters
Safariland 6354DO - ALS Optic Tactical Holster For Red Dot Optic, 6354DO-832-701-MS19-Parent
Safariland 6354DO ALS Optic Tactical Holster for Glock 19 - Milspec Retail
Pistol Holster Red Dot - Tactical 6354do Nylon Holster 3 G17 G19 Glock Pistol X300 - Aliexpress
Safariland 7377 7TS ALS Concealment Belt Loop Holster for Glock 19 - Milspec Retail
Safariland 6354DO-832-701 ALS, Tactical Holster for Red Dot Optic, Rig – Tactical Products Canada