Milwaukee 48-20-4340 Spline Drill Bit 3/4 X 22 Inches

Product Description

The MILWAUKEE 48-20-4340 is a spline-shank rotary hammer drill bit engineered for drilling through brick, block, concrete, and reinforced concrete. The 4-cutter head uses a 4 x 90-degree tip geometry that reduces the risk of locking up when the bit contacts rebar. Patented rebar chamfers extend cutting-edge durability under heavy use. A high-volume flute design clears debris quickly, which helps maintain penetration speed and reduces heat buildup at the cutting face. At 3/4 inch diameter with a 22-inch overall length and a 17-inch drilling depth, this bit handles deep anchor and through-slab applications common in commercial and heavy residential work.

This bit is intended for use in spline-drive rotary hammer tools. It suits applications where large-diameter holes are needed in masonry and concrete, including anchor bolt installation, conduit sleeves, and post installations. The 17-inch drilling depth allows full penetration through thick concrete slabs and CMU block walls without extensions. Licensed electricians, plumbers, and general contractors frequently use bits of this type when setting anchors or running sleeves through structural concrete.

Key Features

• 4-cutter 4 x 90-degree tip geometry reduces lock-up in rebar
• Patented rebar chamfers increase cutting-edge durability
• High-volume flute design accelerates debris removal and lowers heat
• 3/4 inch cutting diameter with 17-inch usable drilling depth
• 22-inch overall length suits deep through-slab and block-wall applications
• Spline shank for use with spline-drive rotary hammer tools

Compatibility

Designed for use with spline-drive rotary hammer tools that accept spline-shank accessories.

Installation Notes

Installation should be performed by a qualified tradesperson familiar with rotary hammer operation and concrete drilling practices. Verify the rotary hammer is powered off and the bit is fully seated in the chuck before beginning. Wear appropriate eye and hearing protection, and follow applicable OSHA guidelines for concrete drilling. Avoid forcing the bit if it contacts dense rebar — allow the cutter geometry to work at controlled speed and pressure.

Technical Specifications

• Cutting Diameter: 3/4 inches
• Overall Length: 22 inches
• Drilling Depth: 17 inches
• Shank Type: Spline
• Cutter Count: 4
• Application: Brick, block, concrete, reinforced concrete
• Weight: 1.66 pounds
• UOM: Each

Standard Information

• Brand: MILWAUKEE
• Manufacturer Part Number: 48-20-4340