Precision Reflex M16-AR15 Upper Receiver Assembly Vise Block Black. Grip this handy block in a bench vice and hold the upper receiver by the lugs or by the receiver rail. It leaves the entire upper receiver accessible to work on sight systems or clean the bore. Constructed of T6 6061 hard coated black anodized aluminum with 2 locator pins and 1 thumb screw for locking the rail into the block. Specifications for Precision Reflex Upper Receiver Assembly Vise Block: Manufacturer: Precision Reflex Finish: Hard Coat Anodized Gun Model: AR-15 Gun Make: AR Platform Fabric/Material: T6 6061 Aluminum Color: Black Features of Precision Reflex M16-AR15 Upper Receiver Assembly Vise Block: Constructed of T6 6061 hard coated black anodized aluminum with 2 locator pins and 1 thumb screw for locking the rail into the block. Package Contents: Precision Reflex Upper Receiver Assembly Vise Block What firearm models does the manufacturer say Precision Reflex Upper Receiver Assembly Vise Block is compatible with? The manufacturer suggests that Precision Reflex Upper Receiver Assembly Vise Block is compatible with AR-15Precision Reflex 05-0083: M16-AR15 Upper Receiver Assembly Vise Block Black