Bosch HC6521 2-1/2-Inch x 18-Inch x 24-Inch Wild Bore Thru-Hole Multi-Cutter Head SDS Max Rotary Hammer Bit, Silver

This works so much better than a Core bit goes in faster and requires less effort!

Works GREAT - does what is needed although the red clay mud can clog it at times. Excellent buy it was $300 cheaper than buying one locally.

Bores holes in basalt rock - off label use but what I needed to do. Holes need frequent cleaning, but it did the job, 20+ 18 inch deep holes and still working fine.

Used commercially. These drill holes in concrete and do a good job unless you hit rebar. It will not cut rebar. They last a long time and are worth the price

I was able to drill 8 holes in solid basalt with this bit. We went a full 24" with the Hilti chuck going into the hole allowing a deeper footing for the uni-strut holding the solar panels. Word of caution: we got stuck two times, the first time because we went too long between vacuuming the debris out of the hole and it built up on the top of the bit and prevented removal of the bit, We removed the hammer and put the vacuum hose down in the shaft of the bit and we were able to clear the blockage. The second time a rock fell into the hole at about 14" of depth and lodged on the top of the bits flanges and the side of the hole, we had to use a smaller roto-hammer and bit and break the problem rock up and retrieve the large bit.

Augering through limestone and this thing gets it done. Still going strong after several holes. Stop often use a shop vac to suck the material out of the hole and use water in the hole to aid in cutting and to keep the bit cooler.

Great for any item that can be moved out the way, through the tilling process. Plugs easily, when in dirt & rocks. The “cup” plugs easily & needs to be cleaned a lot. This adds to the work process.

I used this Bosch Bit to drill into solid concrete for a fence installation utilizing my Bosch Hammer Drill. This bit pulverized the concrete while rotating the material out of the hole. I would highly recommend this bit.