WMD Guns AR-15 Threaded Stripped Upper Receiver - SLAB Style NiB-X Left Hand Silver. Machined from solid 7075 T6 Aluminum and then NiB-X coated for durability and reliability. Machined with M4 ramps. This slick side upper is also perfect for Pistol Caliber AR builds and matches mil-spec lowers. Specifications for WMD Guns AR-15 Threaded Stripped Upper Receiver - SLAB Style: Manufacturer: WMD Guns Caliber: 5.56x45mm NATO Gun Make: AR Platform Gun Model: AR-15 Package Contents: WMD Guns AR-15 Threaded Stripped Upper Receiver - SLAB Style What firearm models does the manufacturer say WMD Guns AR-15 Threaded Stripped Upper Receiver - SLAB Style is compatible with? The manufacturer suggests that WMD Guns AR-15 Threaded Stripped Upper Receiver - SLAB Style is compatible with AR-15WMD Guns 1-NIBXUB-SLAB-LH: AR-15 Threaded Stripped Upper Receiver - SLAB Style NiB-X Left Hand Silver