For precise, consistent OAL handloads, the internals of the Whidden Seater Die are designed to keep your rounds a |. Round. Inside the die is a floating sleeve system helps to improve concentricity - a must for repeatable precision. The Micrometer Adjustable Seating Die has flutes for precise hand adjustment at the loading bench. The depth increments are easily read and will stay that way for years of use. Mfg: Whidden Gunworks