The Battle Arms Lightweight Lower/Upper Receiver Set provides a unique foundation for your first or next build. The Upper and Lower Receivers are cnc machined from 7075-T6 Aluminum and have a patent pending design that makes the receiver exceptionally light weight. Compatible with Mil Standard parts, this receiver is sure to catch eyes. FeaturesLowerDimensional Accuracy InspectionAll Sharp Edges De-Burred Sharp by HandPictograph Selector Markings Properly Marked for 90Adeg Safety or BAD-ASS-ST / BAD-CASS-ST Short Throw Ambidextrous Safety SelectorsReceiver Safety Selector Hole & Internal Wall Machined with Relief Cut for Battle Arms Development "SHORT-THROW / REVERSIBLE" Ambidextrous Safety SelectorsMulti Caliber Marking for Build VersatilityFlared, Deep Beveled Magazine wellEasy 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 GuardUpperPrecis...