The Dormer Pramet C407 20.0 mm HSS-E-Powder Metallurgical Primax Flatted Shank Multi-Flute Roughing end mill is built for efficient, high-volume roughing in steel and alloy family metals. Designed for shoulder milling, slot milling, and ramping, it delivers strong performance in demanding machining environments.

• Diameter: 20.0 mm
• Length of cut: 38 mm
• Overall length: 104 mm
• Reach with neck relief: 53.5 mm
• Shank: Weldon, 20 mm
• Flutes: 4
• Coating/material: Powder metallurgical HSS-E with bright finish
• NRA profile: Asymmetrical coarse pitch for aggressive material removal
• Helix rake: 35° helix and 12° rake angle for efficient cutting in shoulder, slot milling, and ramping
• Standard: DIN 844 K
• Flatted shank: Primax flatted design for improved grip and torque transmission
• Applications: Shoulder milling, slot milling, and ramping across steel, cast steel, ferritic, martensitic, and super‑austenitic stainless steels, duplex or precipitation hardening stainless steels, cast iron, copper or copper alloys, and high‑temperature alloys

This end mill pairs a robust 4‑flute configuration with a powder metallurgical HSS‑E substrate, delivering enhanced wear resistance and edge retention for repeated roughing passes. The NRA asymmetrical coarse pitch profile reduces cutting forces and promotes steady chip evacuation, helping maintain dimensional accuracy and surface quality during aggressive material removal. The 20 mm Weldon shank, combined with the flatted shank design, ensures reliable clamping and torque transfer in standard milling holders, while the bright finish aids in heat dissipation and chip flow. Ideal for operators tackling heavy roughing tasks in a broad range of steels and nickel‑based alloys, it’s a dependable choice for efficient pocketing, ramping, and rough cavities.