SADLAK Picatinny Rail Gas Block High Profile .936 Bore Diameter Black Hardcoat. 040" Aluminum .936 Bore Diameter Clamp type with #10 socket screws and finish with a Black Hard-Coat. Specifications for SADLAK Picatinny Rail Gas Block: Manufacturer: SADLAK Color: Black Coating: Black Hard-Coat Fabric/Material: Aluminum Gun Make: Universal Gun Model: AR-15 Features of SADLAK Gas Block w/Picatinny Rail All of SADLAKs Gas Blocks are made in specialized factories by craftsmen with years of experience delivering consistent quality. All the bores are precision honed and all critical measurements are 100percent inspected to insure consistancy and quality. Package Contents: SADLAK Picatinny Rail Gas Block What firearm models does the manufacturer say SADLAK Picatinny Rail Gas Block is compatible with? The manufacturer says that SADLAK Picatinny Rail Gas Block is compatible with AR-15SADLAK GB220H: Picatinny Rail Gas Block High Profile .936 Bore Diameter Black Hardcoat