Amoolo 3/8-Inch Cobalt Drill Bit Set (5-Pack) – M35 HSS for Hard Metals, Stainless Steel & Cast Iron

Amoolo 3/8-Inch Cobalt Drill Bit Set: Power and Precision for Hard Metals

Meet the Amoolo 3/8-inch cobalt drill bit set—a five-piece collection designed to tackle hard metals with reliability and control. Built with M35 cobalt high-speed steel and a durable 3/8-inch diameter, these bits are sized for common power drills and demanding jobs, from stainless steel to cast iron. The flute length of about 92 mm gives you ample bite length for deeper holes while preserving balance in your drill.

Why cobalt matters

The alloy contains 5% cobalt, which enhances hardness and wear resistance compared to standard HSS bits. In practice, you may notice prolonged sharpness and consistent cutting across multiple holes in tough workpieces.

Smart geometry for precise starts

Each bit is fully ground for a clean cutting edge. The 135° split point helps start the hole accurately and reduces walk, even when you’re working without a center punch. The straight shank is compatible with most chucks, making setup quick.

Versatility across materials

• Hard metals: stainless steel, carbon steel, sheet metal, and cast iron.
• Non-metal and softer materials: plastics, aluminum alloys, wood, and other softer metals.

Real-world use scenarios

From repairing machinery to assembling metalframes, these bits deliver reliable performance with crisp holes. The combination of hardness and balance helps you work with confidence on busy projects, while the five-piece set keeps options clean and organized.

Best practices for longevity

• Use appropriate speeds and moderate pressure to minimize heat buildup.
• Pause to cool after several holes and clear chips to maintain cutting efficiency.
• Wear eye protection and follow standard workshop safety guidelines.

Warranty and support

Amoolo backs this set with a 90-day warranty. If you’re not satisfied, contact for a refund or replacement; this offers practical assurance for your workshop toolkit.