Milwaukee 48-89-2318 Cobalt Drill Bit 21/64 in 3 Pack

Product Description

The MILWAUKEE ELECTRIC TOOL CORP 48-89-2318 is a cobalt drill bit designed for drilling through hard metals, stainless steel, cast iron, and other tough materials. Part of the RED HELIX cobalt series, this 21/64-inch bit features a high-cobalt steel construction that resists heat buildup during extended drilling operations. It is sold in a pack of three, making it practical for job-site use where bit wear is a routine factor. Licensed tradespeople including HVAC techs, plumbers, electricians, and general contractors rely on cobalt bits like this one when standard HSS bits fall short on hardened or abrasive stock.

This drill bit is well suited for metal fabrication, mechanical work, and trade applications that require consistent performance on ferrous and non-ferrous hard metals. The 21/64-inch diameter is a common size for bolt clearance holes and stepped drilling applications in sheet metal, structural steel, and pipe work. The three-unit pack format supports tool crib stocking and service van inventory without overbuying.

Key Features

• 21/64-inch diameter for precision hole sizing in metal applications
• Cobalt steel construction handles high heat and resists wear on hard materials
• RED HELIX geometry promotes chip evacuation and reduces walking on flat stock
• Sold as a 3-pack for practical job-site replenishment
• Lightweight at 0.27 pounds per pack, easy to store and transport

Compatibility

Designed as an OEM-style replacement cobalt drill bit compatible with standard 3/8-inch and 1/2-inch keyed or keyless drill chucks used across corded and cordless drills common in trade applications.

Installation Notes

Cobalt drill bits should be installed by securing firmly in the drill chuck before use to prevent slipping under torque. Always wear eye protection and secure the workpiece before drilling. Cutting fluid or oil is recommended when drilling through thick steel or stainless to extend bit life and manage heat. Follow applicable safety codes and employer guidelines for portable power tool operation on the job site.

Technical Specifications

• Drill Bit Diameter: 21/64 inches
• Material: Cobalt Steel
• Package Quantity: 3 pieces
• Unit of Measure: EA
• Package Weight: 0.27 pounds

Standard Information

• Brand: MILWAUKEE ELECTRIC TOOL CORP
• Manufacturer Part Number: 48-89-2318