Guntec USA AR-15 Gen 2 Clamp On Aluminum Rail Height Gas Block Cerakote Flat Dark Earth. 750 Diameter Gen 2 Two Screws On Side To Compress Against Barrel Easy Install T6 Aluminum Rail Height Roll Pin Included Specifications for Guntec USA AR-15 Clamp On Aluminum Rail Height Gas Block Gen 2: Manufacturer: Guntec USA Caliber: .223 Remington Gun Make: AR Platform Gun Model: AR-15 Weight: 2.4 oz Package Contents: Guntec USA AR-15 Clamp On Aluminum Rail Height Gas Block Gen 2 Roll Pin What firearm models does the manufacturer say Guntec USA AR-15 Clamp On Aluminum Rail Height Gas Block Gen 2 is compatible with? The manufacturer says that Guntec USA AR-15 Clamp On Aluminum Rail Height Gas Block Gen 2 is compatible with AR-15Guntec USA GT750RC-FDE: AR-15 Gen 2 Clamp On Aluminum Rail Height Gas Block Cerakote Flat Dark Earth