Having the right tool for the job makes any gunsmithing project so much easier. The X-Block bench block has both a "V" slot and a rounded slot running across the face of the block to support a variety of barrels and slides. The block is made of a tough, non-marring, polymer, and edged with a softer non-slip outer overmold. Its large 5" diameter provides a stable base with plenty of support. It utilizes a molded in magnet on the back side of the block to catch pins and other small parts as they drop out and has multiple holes to take on almost any project.