This is a drop leg holster platform from Safariland. Attaches to the users belt and then is secured around the thigh with an adjustable buckled strap.
Anti-slip Elastic Gun Holster Strap Drop Leg Holster Thigh Strap QLS 19 22 Mid-low Belt Loop for Glock SIG - AliExpress
Safariland™ Drop Leg Holster Adaptor
Connecting safariland holster to drop leg platform do I need to remove the t nuts from the platform? Instructions not helpful and can't get holster connected. : r/tacticalgear
Safariland STI 1911 Drop Leg Holster Coyote Brown W/ QLS
SAFARILAND HOLSTER SINGLE LEG STRAP And ADAPTER
SAFARILAND Drop Flex Adapter with Single Strap Leg Shroud for Gun Holsters, Assembly Polymer,Black : Safariland Drop Leg Platform : Sports & Outdoors
Guayma Drop Leg Holster Adapter Duty Belt Accessories for QLS Kit,Modular Holster Adapter with Thigh Strap Airsoft Tactical Gear,Black : Sports & Outdoors
SAFARILAND HOLSTER SINGLE LEG STRAP And ADAPTER
Safariland Drop Leg Holster With QLS Plate [Genuine Issue]