BATTLEARMS XIPHOS Dedicated Lower ReceiverUses GLOCK Magazines - Small Frame Glock CalibersIs not compatible with CMMG Delayed Blowback systems that use an "AR Style" magazine and Bolt Carrier Group.FEDERAL FIREARMS LICENSE REQUIRED**PLEASE REFER TO FOOTNOTES BEFORE PURCHASINGSpecifications: 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 90deg 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 All Components, material, and packaging made in the USA MRB (Magazine release block) conversion machined into the lower from factory DISCLAIMER: This product is not manufactured, authorized, endorsed, or warranted by GLOCK. GLOCK does not warrant or represent that this product is compatible with GLOCK pistols.