Milwaukee 48-20-4137 Spline Drill Bit 1-3/8 X 16 in 2-pack

Product Description

The MILWAUKEE 48-20-4137 is a spline-shank rotary hammer drill bit designed for heavy-duty concrete and masonry drilling. Sold as a 2-count pack, each bit measures 1-3/8 inches in diameter and 16 inches in length, making it well suited for deep-bore applications in reinforced concrete, block, and stone. The spline drive shank interfaces directly with spline-drive rotary hammers, transferring high impact energy efficiently into the material without slippage at the chuck. This bit is a standard tool for licensed contractors, concrete finishers, and skilled tradespeople who require consistent hole diameters through structural substrates.

This bit is used in commercial and residential construction applications where large-diameter, deep concrete penetrations are required — anchor bolt installations, conduit sleeves, rebar clearance holes, and structural core work. The 16-inch working length provides reach through thick slab sections or block walls without requiring extensions. The 2-count pack supports continued productivity when one bit is in service and a backup is needed on the job site.

Key Features

• 1-3/8-inch cutting diameter for large-bore concrete and masonry applications
• 16-inch length provides deep reach through thick slabs and block walls
• Spline drive shank for use with spline-drive rotary hammers
• 2-count pack included per unit
• Designed for rotary hammer drilling in reinforced concrete, block, and stone

Compatibility

Designed for use with spline-drive rotary hammers. Verify that your rotary hammer accepts a spline drive chuck before installation.

Installation Notes

Installation is performed by qualified tradespeople using a compatible spline-drive rotary hammer. Before inserting or removing the bit, confirm the hammer is powered off and disconnected from its power source. Insert the spline shank fully into the chuck and confirm it is seated and locked per the hammer manufacturer's guidance. Inspect the bit for cracks or excessive wear before each use and replace if damaged.

Technical Specifications

• Cutting Diameter: 1-3/8 inches
• Bit Length: 16 inches
• Shank Type: Spline Drive
• Quantity per Pack: 2
• Weight: 2.76 pounds
• UPC: 0045242103201

Standard Information

• Brand: MILWAUKEE
• Manufacturer Part Number: 48-20-4137