Milwaukee 48-89-2731 Thunderbolt Black Oxide Drill Bit, 25/64 In., Jobber

The Milwaukee 48-89-2731 Thunderbolt Black Oxide Drill Bit is a 25/64-inch jobber-length bit engineered for general-purpose drilling in wood, metal, and PVC. The black oxide coating reduces friction, resists corrosion, and extends bit life in demanding applications. This bit requires less effort to drill through these materials compared to standard drill bits.

The Thunderbolt design features a thicker web core than standard drill bits, providing superior strength and protection against side-load breakage—a critical advantage when drilling at angles or on curved surfaces. The parabolic flute geometry clears chips away from the cutting zone. The 3-flat Secure-Grip shank holds the bit firmly in the drill chuck. The 135-degree split-point tip delivers precision entry without walking, eliminating the need for pilot holes and producing clean, accurate holes on the first attempt.

Features and Benefits

• Black Oxide Coating: Reduces friction, adds lubricity, and resists corrosion for extended service life.
• Thicker Core Design: The Thunderbolt web provides ultimate strength and protects against side-load breakage during angled or curved drilling.
• Parabolic Flute: Clears chips from the cutting zone for efficient drilling.
• 3-Flat Secure-Grip Shank: Holds the bit firmly in the chuck.
• 135-Degree Split-Point Tip: Delivers precision starts with no walking, producing clean holes without pilot holes.
• Versatile Material Compatibility: Effective on wood, metal, PVC, and curved surfaces with less drilling effort required.

Specifications

• Brand: Milwaukee
• Model: 48-89-2731
• Bit Diameter: 25/64 inch
• Overall Length: 5-1/8 inches
• Bit Type: Jobber bit
• Shank Diameter: 3/8 inch
• Flute Design: Parabolic flute
• Tip Style: 135-degree split point
• Coating: Black oxide
• Packaging: Skin carded