The Ultra Micrometer Seater Die is a non-crimping style seater die (except for the 30-30) that holds the bullet and case in perfect alignment while the bullet is press-fit seated. A handy micrometer fixes the bullet seating depth to your specifications. After you have seated your bullet close to the desired depth and measured it, simply adjust the Micrometer stem up or down to the desired depth and the cartridge will be exactly the length you need. The non-crimping style provides accuracy, consistency, and virtually flawless alignment.