Tiger Rock Upper Receiver AR-9 Enhanced 9mm AR-15 Billet Black Small. This upper was designed to do away with the traditional forward assist and dust cover. This has been done to save weight as well as improve functionality and reliability by focusing on a simple design. Specifications for Tiger Rock AR-9 Enhanced 9mm AR-15 BILLET Upper Receiver: Manufacturer: Tiger Rock Caliber: 9mm Luger Finish: Anodized Color: Black Fabric/Material: 7075-T6 Aluminum Gun Rail: Picatinny Gun Type: Rifle Gun Make: AR Platform Gun Model: AR-15 Condition: New Magazine Included: No Features of Tiger Rock AR-9 Enhanced 9mm AR-15 BILLET Upper Receiver Slick Side No Forward Assist Flat-Top with Picatinny rail Package Contents: Tiger Rock AR-9 Enhanced 9mm AR-15 BILLET Upper Receiver What firearm models does the manufacturer say Tiger Rock AR-9 Enhanced 9mm AR-15 BILLET Upper Receiver is compatible with? The manufacturer says that Tiger Rock AR-9 Enhanced 9mm AR-15 BILLET Upper Receiver is compatible with AR-15Tiger Rock AR9-UPPER-BILLET: Upper Receiver AR-9 Enhanced 9mm AR-15 Billet Black Small