The 280 Remington Gold Medal Match Series comprises the finest reloading dies built by RCBS. The Neck Bushing Sizer Die resizes only the case neck, and its changeable diameter neck bushing design has been trusted by benchrest and long-range precision shooters for years. It lets reloaders precisely set the amount of tension on the bullet, reducing work-hardening of the case neck brass, prolonging case life and increasing accuracy. However, getting these benefits requires the use of high-end brass with consistent neck thicknesses. Neck bushings (sold separately) are available in .001-inch increments from .189-inch to .365-inch. Note: Neck Bushings are not included. Mfg: Rcbs