The Swage Support Die is compatible with the Frankford Arsenal X-10 Progressive Press along with any other reloading system utilizing inline swaging. If running multiple X-10 Tool Heads, the user can leave this die fully setup on their Tool Head making it quick and easy to make caliber swaps. Features: For use with x-10 progressive press or other reloading systems that utilize inline swaging Standard 7/8"X14 threads Leave installed on x-10 tool head for fast caliber swaps