AIM Sports Inc AR Upper Receiver Vise Block Black Medium. These Receiver Vise Blocks & Reaction Rods from AIM Sports Inc are made of solvent resistant polymer construction and allow safe clamping of the upper receiver into a vise. The AIM Sports Inc AR Upper Receiver Polymer Vise Block is ideal for repair service or when assembling a weapon. Specifications for AIM Sports Inc AR Upper Receiver Vise Block: Manufacturer: AIM Sports Inc Gun Make: AR Platform Gun Type: Rifle Color: Black Condition: New Length: 4.5 in Features of AIM Sports Inc AR Upper Receiver Vise Block Perfect for cleaning service or weapon assembly Will not crush distort mar or damage the receiver Solvent resistant polymer construction Package Contents: AIM Sports Inc AR Upper Receiver Vise Block AIM Sports Inc ATUVB: AR Upper Receiver Vise Block Black Medium