The Lee Precision Part LEE 92374 is a 6mm ARC Micrometer Full Length 2-Die Set. It includes everything you need to reload mixed-range 6mm ARC brass: [1, 2] Full Length Sizing Die: Resizes spent brass back to factory dimensions. Micrometer Bullet Seating Die: Features a laser-engraved adjustment dial for ultra-precise, mark-free bullet seating depth. Accessories: Universal shell holder, powder measure/scoop, and load data Floating Bullet Guide: Centers both the case mouth and the projectile for perfect alignment and reduced bullet runout. Dead-Length Seating: The die contacts the shell holder to ensure uniform seating depth on every press stroke. Versatile Crimping: The seater sleeve can be reversed to simultaneously seat and crimp in a single operation