This is a special Dovelock master jaw set that we use with the Kurt Dx6 cross vise. Our family no longer has active machinists, but there is plenty of equipment. The only active locksmith in the family has now become the most passionate person who likes to experiment with tools. Many of us have many tools from different brands, including high-quality Kurt, a more professional brand than the one used by many. visual effects with instructions. Figuring out how to install the jaws wasn't difficult