Milwaukee 48-20-4125 Spline Drill Bit 1-1/4x16 in 2-pack

Product Description

The MILWAUKEE 48-20-4125 is a spline-shank rotary hammer drill bit designed for heavy-duty core and anchor hole drilling in concrete, masonry, and block. Measuring 1-1/4 inches in diameter and 16 inches in length, this bit is sold as a 2-count pack, making it a practical choice for crews working multiple holes in a single job. The spline drive interface transfers rotational torque and hammering force efficiently from the rotary hammer to the bit, reducing operator fatigue during extended drilling runs. Licensed HVAC, plumbing, and electrical contractors commonly use bits in this size range when core-drilling through concrete slabs or masonry walls to route conduit, pipe, or duct penetrations.

This bit is sized for penetrations requiring a 1-1/4-inch diameter bore through reinforced or unreinforced concrete and masonry substrates. Typical install scenarios include anchor-bolt hole prep, through-slab utility penetrations, and structural core drilling on commercial and residential job sites. The 16-inch working length provides sufficient reach for thick poured-concrete walls and block foundations common in commercial construction. The 2-count configuration supports back-to-back use without halting work to locate a replacement bit.

Key Features

• 1-1/4-inch cutting diameter for standard utility penetration sizing
• 16-inch working length for deep concrete and masonry applications
• Spline drive shank for compatibility with spline-drive rotary hammers
• 2-count pack reduces downtime on multi-hole applications
• Designed for rotary hammer use in concrete, block, and masonry

Compatibility

Designed for use with spline-drive rotary hammers. No specific compatible model numbers were provided in the product data.

Installation Notes

Installation of this bit requires a spline-drive rotary hammer — do not attempt to use a spline shank in an SDS-plus or SDS-max chuck without an appropriate adapter. Before drilling, verify the work area for embedded rebar, conduit, or post-tension cables using a scanning tool, as required by most site safety codes. Secure the workpiece or mark the drill point clearly before applying hammer-drill force. Inspect the bit for carbide tip wear or shank damage before each use and replace if chipping or deformation is present.

Technical Specifications

• Cutting Diameter: 1-1/4 inches
• Bit Length: 16 inches
• Shank Type: Spline Drive
• Package Quantity: 2 per pack
• Package Weight: 2.26 pounds
• Package Height: 18.07 inches
• Package Width: 1.56 inches
• Package Length: 1.56 inches
• UPC: 0045242103102

Standard Information

• Brand: MILWAUKEE
• Manufacturer Part Number: 48-20-4125