Battle Arms Development XIPHOS AR-9 Glock Lower Firearm Receiver Multi Colored Black. Is not compatible with CMMG Delayed Blowback systems that use an ''AR Style'' magazine and Bolt Carrier Group. Specifications for Battle Arms Development XIPHOS AR-9 Glock Lower Firearm Receiver: Manufacturer: Battle Arms Development Firearm Receiver Color: Black Gun Make: Battle Arms Development Caliber: 9mm Luger Features of Battle Arms Development XIPHOS AR-9 Glock Lower Firearm Receiver: Precision CNC from Billet 7075-T6 Aerospace Aluminum Patent Pending Lightweight Design Laser Engraved Logo MIL-A-8625F Type III Class 2 Hard Anodized Black Finish Compatible with TDP/Mil Standard AR Lower Receiver Parts Dimensional Accuracy Inspection All Sharp Edges De-Burred Sharp by Hand Pictograph Selector Markings Properly Marked for 90 Safety or BAD-ASS-ST / BAD-CASS-ST Short Throw Ambidextrous Safety Selectors Receiver Safety Selector Hole & Internal Wall Machined with Relief Cut for Battle Arms Development ''SHORT-THROW / REVERSIBLE'' Ambidextrous Safety Selectors Multi Caliber Marking for Build Versatility Flared Deep Beveled Magazine well Easy in Install Set Screw Bolt Catch Pin (Pin Included) Captured Takedown Pin Detent Spring (Set Screw Included) Upper/Lower Receiver Tension Screw (Screw included) Integrated Trigger Guard MRB (Magazine release block) conversion machined into the lower from factory Package Contents: Battle Arms Development XIPHOS AR-9 Glock Lower Firearm Receiver Battle Arms Development XIPHOSLR: XIPHOS AR-9 Glock Lower Firearm Receiver Multi Colored Black