11/16 in Cobalt Drill Bits 3 Pack - M35, 6 in Length

Our review finds these 11/16 in cobalt drill bits best suited for metalworkers and serious DIYers who need reliable, repeatable holes in hard materials; the single biggest reason to buy is the combination of M35 construction with a 135 split point that starts accurately and maintains cutting performance across tougher metals. In this review the set's 6 in total length and 3 in flute give reach and chip clearance, while the included plastic storage case keeps the three bits protected when not in use.

Key Features

• M35 with 5% cobalt: Adds hardness and heat resistance so the bits stay sharper longer when drilling stainless and hardened steel.
• 11/16 in diameter: Provides a consistent hole size for fittings and fasteners commonly used in metal fabrication and repairs.
• 3 in flute, 6 in total length: Offers extra reach and chip evacuation for deeper holes without sacrificing control.
• Fully ground, 135 split point: Helps the bit self-center and reduces walking for more accurate, repeatable holes in hard materials.
• Plastic storage case included: Keeps the three bits organized and protected from knocks and moisture between jobs.
• Narwhal guarantee: USA based customer service is available if any issue arises with the set.

Who It's For

This set is aimed at professionals and hobbyists who frequently drill stainless steel, hardened steel, cast iron, titanium, bronze and similar metals and need a durable, precision 11/16 in option. The extra length and split point make these drill bits a good match when working on sheet metal, thicker plates, or components that require a clean, accurate hole.

Those who mainly drill wood, soft plastics, or only occasional small-diameter holes should look elsewhere for a less aggressive, lower-cost bit optimized for softer materials; likewise, users needing metric sizes or a wide assortment of diameters will want a larger multi-size kit.

Pros & Cons

Pros

• Good cutting performance and sharpness reported by customers, slicing aluminum and similar alloys cleanly.
• Solid M35 construction with 5% cobalt that improves durability and heat tolerance.
• Long 6 in length with 3 in flute gives extra reach and better chip removal for deeper holes.
• Handy plastic storage case keeps the set organized and protected.

Cons

• Durability feedback is mixed; some users report breakage under aggressive use, so proper feed rates and coolant are recommended.
• Only three identical-size bits are included, so this set does not replace a full-size assortment.

Specifications

Our Verdict

These 11/16 in M35 cobalt drill bits are a sensible purchase for metalworkers who need a reliable, longer bit that starts well and handles hard materials. They offer strong value when used with appropriate technique and cooling, though buyers wanting a wide range of sizes or bits dedicated to wood should consider other kits.

Frequently Asked Questions

Are these bits good for stainless steel?
Yes, the M35 construction and 5% cobalt make them suitable for stainless and other hardened metals when used with correct speed and lubricant.

Do they come with a case?
Yes, a durable plastic storage case is included to keep the three bits organized and protected.

Will these break easily?
Some customers reported breakage under extreme stress; using proper feed rates, pilot holes when appropriate, and coolant reduces the risk of breakage.