Geissele Gas Block Roll Pin Tool 10-225 is a specialized gunsmithing aid designed to securely hold a 0.078? diameter roll pin during installation into an AR gas block. Made in the USA from hardened steel, this tool simplifies one of the trickiest parts of assembly by allowing you to press-fit the pin into the block cleanly before final seating with a punch. Material: hardened steel (black finish) Made in USA with precision machining Fits standard 0.078? diameter AR gas block roll pins Small tip hole holds the pin securely during installation Weighs only ~1.6oz, highly portable and simple to use Geissele Gas Block Roll Pin Tool 10-225