The Redding #12 Competition Shell Holder Set provides precision reloaders with complete control over headspace adjustment through five shell holders sized in 0.002-inch increments.Redding #12 Competition Shell Holder Set5-piece set with 0.002-inch incremental sizingEach shell holder clearly marked for headspace reduction amountPrecise case-to-chamber headspace controlHeavy-duty plastic storage box includedEssential for competitive shooters and precision reloaders who demand consistent cartridge dimensions and optimal chamber fit for maximum accuracy.