REPLACEMENT COMPONENT ONLY - This Area 419 Zero M-Series sizing insert is designed for existing M-Series die owners and provides 300 PRC caliber capability with precision reamer-cut sizing chambers.Area 419 Zero M-Series Sizing Sleeve for 300 PRCIncludes mandrel with approximately 0.002" neck tensionExtra decapping pin includedReamer-cut sizing chamber for full case body sizingCompatible only with existing M-Series die systemsModular design for caliber flexibilityPerfect for serious reloaders who own Area 419 M-Series dies and want to add 300 PRC capability to their precision reloading setup. Features the same quality construction and micrometer headspace adjustability as complete M-Series dies.