The Diablo DMAMX1250 1-1/8 in. x 8 in. x 13 in. Rebar Demon SDS-Max 4-Cutter Full Carbide Head Hammer Drill Bit is built for drilling large, accurate holes in concrete, reinforced concrete, brick, and block. This is a hammer drill bit designed for heavy-duty masonry drilling and anchor setting in tough material, especially where rebar is likely. Model Number: DMAMX1250.

This bit uses an SDS-Max shank and is optimized for corded and cordless SDS-Max rotary hammers. That matters because it is meant for bigger holes and higher-impact work, not light-duty drilling. The 1-1/8 inch diameter, 8 inch working length, and 13 inch overall length make it a strong fit for deeper anchor holes and pass-through work where smaller masonry bits come up short.

The big selling point here is the full carbide 4-cutter head. Instead of a simpler two-cutter layout, the head is built to stay productive when it meets rebar. Diablo says the design takes smaller bites out of rebar for controlled wear, reduced vibration, and faster, more precise holes. In real use, that means less grabbing, less deflection, and a better chance of finishing the hole with the same bit instead of tossing it after one bad hit.

Diablo also leans hard on durability with its Dura-Carbide construction and Tri-Metal Fusion Welding. According to the product data, the bit carries up to 2X more carbide and withstands heat up to 1800 degrees Fahrenheit, compared to standard bits that fail around 800 degrees Fahrenheit. The stronger weld is there for the same reason: when a large rotary hammer is driving into reinforced concrete, the head takes serious abuse. A stronger head-to-body connection helps the bit survive that impact load.

Dust removal is another practical part of the design. The optimized flute is built to clear debris faster, which helps keep the carbide head cooler and the drilling action more efficient. On the job, faster dust evacuation usually means the bit stays cutting instead of rubbing, and that helps hole speed and bit life. Diablo also includes a wear mark indicator to help maintain hole accuracy over time, which is useful when you need consistent anchor depth and diameter.

For buyers comparing masonry drill bits, this is not a general-purpose concrete bit for occasional use. This is a large-diameter SDS-Max accessory meant for serious rotary hammer work in reinforced concrete and other dense masonry. If you regularly hit rebar, drill anchor holes, or need a masonry bit that can handle repeated heavy impact without giving up early, this is the kind of bit worth paying for.

It is best suited to concrete contractors, mechanical crews, commercial installers, masonry trades, and remodelers using SDS-Max rotary hammers. Serious DIY users with the right hammer can use it too, but this bit really makes the most sense for users who drill enough concrete to appreciate longer service life, lower vibration, and better performance when the bit finds steel.

Diablo DMAMX1250 is the right bit when rebar is part of the job

This is the kind of large-diameter masonry bit you buy because downtime and burned-up cutters cost more than the bit does.

• Who it's for: Pros running SDS-Max rotary hammers for anchor setting, commercial installs, and reinforced concrete drilling.
• Why it stands out: The 4-cutter full carbide head, stronger welded construction, and dust-clearing flute are all aimed at surviving rebar hits and keeping holes accurate.
• Worth knowing: This is an SDS-Max bit only, so make sure your rotary hammer matches the shank before you order. It is a specialty hammer drill bit, not a general-purpose drill bit.

• What type of tool does this bit fit? It is designed for SDS-Max rotary hammers, including corded and cordless models.
• Can it drill through rebar? Yes. The bit is specifically designed for concrete with rebar and uses a 4-cutter full carbide head for better durability and control when it hits steel.
• What is the usable drilling depth? The working length is 8 inches, with an overall bit length of 13 inches.
• What materials is it made for? It is intended for concrete, reinforced concrete, brick, and block.