Irwin 3016021 Cobalt Drill Bit 21/64 Inches 5 Pack

Product Description

The IRWIN INDUSTRIAL TOOL CO 3016021 is a 21/64-inch cobalt drill bit engineered for high-performance metal drilling in demanding trade and industrial applications. Constructed with 8% cobalt steel, the bit delivers superior heat and abrasion resistance compared to standard high-speed steel bits, making it well-suited for extended drilling sessions on tough materials. The 135-degree split point tip reduces bit walk on contact, allowing the drill to seat accurately without center-punching. A heavy-duty web construction runs through the body for added strength and durability under load. Sold in a 5-pack.

This cobalt drill bit is designed for drilling hardened steel, cast iron, stainless steel, alloy metals, and other heavy-duty abrasive materials where standard bits fail prematurely. It is a reliable choice for metal fabricators, pipefitters, ironworkers, electricians, and HVAC technicians who regularly drill through structural steel, pipe fittings, enclosures, and plate metal. The 5-piece quantity makes it practical for job-site use where bit wear is expected and replacement availability matters.

Key Features

• 8% cobalt construction for elevated heat resistance and extended bit life in abrasive materials
• 135-degree split point tip minimizes bit walk and eliminates the need for center-punching on hard surfaces
• Heavy-duty web design adds structural rigidity and resists breakage under lateral load
• Rated for hardened steel, cast iron, stainless steel, and alloy metal drilling
• Sold as a 5-piece pack for job-site readiness

Compatibility

Designed as a general-purpose cobalt drill bit for use in standard 3/8-inch and 1/2-inch chuck drills and drill presses capable of accepting a 21/64-inch round shank bit.

Installation Notes

Cobalt drill bits should be installed in a properly rated drill or drill press with a chuck that accommodates the shank diameter. Use appropriate cutting fluid or lubricant when drilling stainless steel or hardened alloys to reduce heat buildup and extend bit life. Ensure the workpiece is securely clamped before drilling to prevent movement. Inspect bits for wear or cracking before each use and replace immediately if damage is found.