






Milwaukee 5/16" Thunderbolt Black Oxide Drill Bit 48-89-2726
REINFORCED CORE TECHNOLOGY FOR MAXIMUM SIDE-LOAD DURABILITY
Standard twist bits often fail at the core when subjected to the lateral pressures of handheld drilling, but the Milwaukee Thunderbolt series is engineered to solve that mechanical weakness. By utilizing a thicker web—the structural spine of the bit—this 5/16" black oxide bit provides significantly higher torsional strength and resistance to breakage. The parabolic flute geometry is specifically designed to eject chips rapidly, preventing the heat buildup that typically dulls cutting edges in high-speed steel. For professionals working on curved surfaces or stainless steel, the 135-degree split point ensures the bit bites immediately on contact, eliminating the need for a center punch and preventing the "walking" that ruins workpieces.
- / Thunderbolt® Web: A thicker core design that provides ultimate strength and protects against breakage from side-load pressure.
- / 135° Split Point Tip: Precision tip starts on contact to prevent bit walking, ensuring fast and accurate hole placement in metal and wood.
- / Parabolic Flute Geometry: Clears chips and debris faster to keep the bit cool and maintain cutting efficiency during extended use.
- / 3-Flat Secure-Grip™ Shank: Engineered with three flat sides to prevent the bit from spinning in the drill chuck under high-torque loads.
- / Black Oxide Coating: Enhances lubricity and provides superior corrosion resistance for a longer professional service life.
TECHNICAL SPECIFICATIONS
| Diameter | 5/16" |
| Decimal Equivalent | 0.3125" |
| Length Type | Jobber |
| Overall Length | 4-1/2" |
| Flute Length | 3-3/16" |
| Point Angle | 135° Split Point |
| Shank Style | 3-Flat Secure-Grip™ |
| Coating | Black Oxide |
| Application | Metal, Wood, Plastic |
WHAT'S IN THE BOX
(1) 5/16" Thunderbolt® Black Oxide Drill Bit (48-89-2726)
Original: $2.79
-65%$2.79
$0.98Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
REINFORCED CORE TECHNOLOGY FOR MAXIMUM SIDE-LOAD DURABILITY
Standard twist bits often fail at the core when subjected to the lateral pressures of handheld drilling, but the Milwaukee Thunderbolt series is engineered to solve that mechanical weakness. By utilizing a thicker web—the structural spine of the bit—this 5/16" black oxide bit provides significantly higher torsional strength and resistance to breakage. The parabolic flute geometry is specifically designed to eject chips rapidly, preventing the heat buildup that typically dulls cutting edges in high-speed steel. For professionals working on curved surfaces or stainless steel, the 135-degree split point ensures the bit bites immediately on contact, eliminating the need for a center punch and preventing the "walking" that ruins workpieces.
- / Thunderbolt® Web: A thicker core design that provides ultimate strength and protects against breakage from side-load pressure.
- / 135° Split Point Tip: Precision tip starts on contact to prevent bit walking, ensuring fast and accurate hole placement in metal and wood.
- / Parabolic Flute Geometry: Clears chips and debris faster to keep the bit cool and maintain cutting efficiency during extended use.
- / 3-Flat Secure-Grip™ Shank: Engineered with three flat sides to prevent the bit from spinning in the drill chuck under high-torque loads.
- / Black Oxide Coating: Enhances lubricity and provides superior corrosion resistance for a longer professional service life.
TECHNICAL SPECIFICATIONS
| Diameter | 5/16" |
| Decimal Equivalent | 0.3125" |
| Length Type | Jobber |
| Overall Length | 4-1/2" |
| Flute Length | 3-3/16" |
| Point Angle | 135° Split Point |
| Shank Style | 3-Flat Secure-Grip™ |
| Coating | Black Oxide |
| Application | Metal, Wood, Plastic |
WHAT'S IN THE BOX
(1) 5/16" Thunderbolt® Black Oxide Drill Bit (48-89-2726)













