The Henderson Precision Gen 4 Taper Lock Case Trimmer Cutter will only fit the Gen 4 trimmer (Not for the Gen 2 or 3 Trimmer). Cutter bodies are machined from 416 stainless steel. The ID chamfer is 14deg and the OD chamfer is 30deg, the blades are made from carbide. The Taper-Lock cutters can be order either factory adjusted or they can be adjusted by the end user. We have videos on our video page that will walk you through the process. The trimmer utilizes a draw screw taper on taper design for precision alignment of the cutting head and shaft. All pilots are Caliber-Specific.