Milwaukee 48-20-4365 Spline Drill Bit 7/8x22 Inch 4CT

Product Description

The MILWAUKEE 48-20-4365 is a spline-shank rotary hammer drill bit engineered for drilling into brick, block, concrete, and reinforced concrete. The 4-cutter tip uses a 4 x 90 degree geometry that resists lock-up when the bit contacts rebar, a common failure point on jobsites. Patented rebar chamfers protect the cutting edges and extend service life. The high-volume flute design clears debris quickly, reducing heat buildup and keeping penetration rates high. At 7/8 inch in diameter and 22 inches in overall length, this bit handles deep anchor, sleeve, and through-bolt hole applications. Licensed tradespeople and commercial concrete drillers are the primary users.

This bit is suited for residential and commercial masonry work where reinforced concrete is present. Typical applications include setting anchor bolts, drilling conduit penetrations through block walls, and creating sleeve holes in poured concrete slabs and foundations. The spline shank is designed for use with spline-drive rotary hammer tools operating in rotary-hammer mode. The 17-inch drilling depth accommodates thick walls and deep embedment requirements without extension hardware.

Key Features

• 4-cutter 4 x 90 degree tip geometry resists lock-up on rebar contact
• Patented rebar chamfers increase cutting edge durability
• High-volume flute promotes fast debris evacuation and reduced heat buildup
• 7/8 inch diameter with 17-inch usable drilling depth
• 22-inch overall length for deep embedment and through-wall applications
• Spline shank for compatibility with spline-drive rotary hammer chucks

Compatibility

Designed for use with spline-drive rotary hammer tools operating in rotary-hammer or hammer-drill mode. Suitable for drilling brick, block, poured concrete, and reinforced concrete applications.

Installation Notes

Installation should be performed by qualified tradespeople familiar with rotary hammer operation and concrete drilling practices. Confirm the tool is set to the correct mode (rotary hammer) before drilling and ensure the bit is fully seated and locked in the spline chuck. Always wear appropriate PPE including eye protection and hearing protection when operating rotary hammer equipment. Inspect the bit for wear or damage before each use and remove from service if cutting edges are chipped or the shank shows deformation.

Technical Specifications

• Shank Type: Spline
• Tip Configuration: 4-Cutter, 4 x 90 degree geometry
• Diameter: 7/8 inch
• Overall Length: 22 inches
• Drilling Depth: 17 inches
• Weight: 2.03 pounds
• UOM: Each
• UPC: 0045242103669

Standard Information

• Brand: MILWAUKEE
• Manufacturer Part Number: 48-20-4365