This is a 1-1/4a ^2 die and requires a Hybrid or 1-1/4a ^2 Turret on your ZERO (or other press). It CANNOT be used with a 7/8a ^2 Turret or other 7/8a ^2 press.IMPORTANT NOTE - THESE DIES ARE NOT COMPATIBLE WITH STANDARD SHELLHOLDERS AND REQUIRE A LARGER DIAMETER SHELLHOLDER RIM. IF YOU DO NOT HAVE A ZERO M-SERIES SHELLHOLDER YOU CANNOT USE THIS DIE. The ZERO M-Series Sizing die is the culmination of years of testing research trial error frustration and finally discoveries.As Reloaders AREA 419 knew they needed a die to do certain things but as the makers of the ZERO Reloading Press they also learned a huge amount about what other dies did well or did poorly and what their customers were struggling with on a daily basis.With the ZERO M-Series Sizing Die AREA 419 produced a sizing die that is capable of producing the finest match-grade ammunition as well as being user-friendly to new and learning reloaders.Sizing brass doesn't have to be complicated. It doesn't have to require years of trial and error. It just needs equipment made with the end-user in mind designed with the understanding that a die is part of an ecosystem of parts. A press a die the brass the rifle - they all have to work together and be designed with one another in mind. This is that. Introducing the ZERO M-Series Sizing Die.KEY FEATURES Micrometer Adjustable Headspace/Shoulder Bump Precision Ground Expander Mandrels (all dies ship with a .002 neck tension mandrel or add more increments with the AREA 419 Mandrel Kit Full-Length Neck to Extractor Sizing Spring Ejection for Spent Primers Replaceable Steel Decap Pins Reamer Cut to Exacting Dimensions for a TRUE Size (no more sticky bolt after the second firing) Hydraulic Shoulder Pressure Relief 100% Made in AMERICAAll dies ship with an Area 419 ZERO Die Ring a spare decapping pin and necessary install/removal tools.