The Henderson Precision Gen 3 Taper-Lock Cutting Head trims overall length as well as chamfers both the inside and outside of the case. The carbide blades are extremely repeatable and bullet proof. 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 trimmer utilizes a draw screw taper on taper design for precision alignment of the cutting head and shaft. All pilots are Caliber-Specific. Note:Taper-Lock cutting heads will only fit the ELR Gen 3 trimmer with the Taper-Lock shaft (Not for the Gen 2 Trimmer). Blades are not pre-adjusted and will need to be done by the end user. There is a QR code on the cutter head box that takes the customer to video page for instructions.