This 2-Die Set is specifically designed for reloading bottleneck cases. It includes a Full-Length Sizer Die with an Expander-Decapping Unit and a Seater Die with a Bullet Seater Plug. The Full-Length Sizer Die is engineered to bring the case to SAAMI minimum cartridge dimensions, ensuring precise sizing. It works by sizing the outside of the case, de-priming and expanding the neck to accept the bullet. The die also features vents to prevent damage from trapped air or excessive lubricant during resizing. It holds headspace to minimal tolerances, preventing any alteration to the case body length during the full-length sizing process. The Seater Die comes equipped with a built-in roll crimper to securely hold the bullet in place while it's seated, ensuring consistent and reliable performance.