The Dormer Pramet C618 5/16 Inch HSS-E Flatted Shank End Mill is a reliable, four-flute cutting tool designed for precise shoulder milling, slot milling, and ramping in steel and copper alloys. Built for machinists who need consistent performance and long tool life in small-diameter pockets and tight tolerances.

• Diameter: 5/16" (0.3125 in)
• Flutes: 4-flute design for efficient cutting and steady chip evacuation
• Length of cut: 3/4" (0.75")
• Overall length: 2-1/2" (2.5")
• Shank: 3/8" Weldon shank for secure, repeatable clamping
• Material: HSS-E cobalt-based with bright finish for enhanced wear resistance and heat tolerance
• Helix angle: 30° to promote smooth entry and effective chip flow
• Standards: ANSI standard dimensions for compatibility with common toolholders
• Primary applications: Shoulder milling, slot milling, and ramping in free-machining and plain carbon steels, copper and copper alloys

The 4-flute geometry paired with cobalt-based HSS-E delivers robust performance under demanding cut conditions, helping achieve clean finishes and longer tool life. The combination of a 30° helix and a Weldon shank provides stable operation, precise pocketing, and dependable repeatability in everyday milling tasks. Ideal for shops prioritizing reliability in small-diameter work, this end mill supports efficient material removal in free-machining steels and copper alloys without compromising precision.