Spring-loaded center pin for positive alignment and holding power. Mounts to 4-Jaw Chuck for turning between centers. The 4-Prong Drive Center has 4-Prongs for strong grapping power on large projects and soft woods. These lathe accessories were designed with the turner in mind. Our focus was to provide a quick and easy way for turners to keep their chucks on the lathe with these products, from a brand you know and trust.