When you need to conquer deep-hole drilling with reliability, the Dormer Pramet A125 9.00 mm x 400 mm HSS ST Straight Shank Extra Long Series drill is purpose-built for the job. This single, long-reaching bit blends precision ground geometry with robust materials to tackle demanding applications without compromise.

• 118-degree conventional point — A strong, easily re-grindable point that starts holes cleanly and reduces wandering, even in tough metals. This geometry helps you achieve accurate first hits and smoother chip evacuation on every pass.
• Steam oxide finish — The protective coating minimizes built-up edge and prevents workpiece material from sticking to the cutting edge, promoting steadier feeds and longer edge life in steel, aluminum, and stainless steel.
• Extra Long length series (400 mm) — Precisely engineered for drilling very deep holes and for situations where reach matters. With this extended flute length, you can access recessed features, thick workpieces, or assemblies where standard bits fall short.
• Premium HSS material — High-speed steel delivers dependable wear resistance and toughness, making it suitable for a broad range of materials including steel, aluminum, and stainless steel. It’s the versatile workhorse you can reach for again and again.
• Versatile applicability — Designed to perform across a variety of machines and setups, from conventional drill presses to CNC and manual milling operations. It’s a practical, one-tool solution for diverse fabrication tasks.

Whether you’re fabricating automotive components, crafting machinery housings, or drilling through multi-layer assemblies, this A125 drill bit provides consistent hole quality, dependable longevity, and the reach needed for challenging layouts. The 9.00 mm diameter and 400 mm length strike a balance between rigidity and depth, making it a trusted choice for shops that value precision with practical, long-reach capability.

Ideal use cases

Deep-hole through-holes in steel, aluminum, and stainless steel; reaching features inside boxes, frames, or structural components; and any project where standard-length bits can’t access the desired hole depth. Pair with appropriate drill speeds and lubrication to maximize edge life and chip clearance.