The Lee Precison Full Length 300 AAC Blackout is for use with 300 AAC Blackout and includes a die box. Lee Full Length Sizer Dies are built to last a lifetime and are great at producing factory like ammunition. Lee Precision has been manufacturing high quality, affordable reloading equipment since 1958. The Lee Sizing die is no exception. These steel sizing dies require the use of a quality resizing lubricant. Shellholders are sold separately.