BOSCH HC8517 2-1/4-Inch X 22-Inch SDS-Max Rotary Hammer Core Bit, Gray

I bought 2 of these! A little disappointed with the grip of the carbide tips but I must admit that I gave them a hard time!! When used in new condition, it performs very well but as it drops off the peaks, the performance decreases rapidly. I am still satisfied with his performance with what I put them through!

Muy buena calidad y muy rapido

Perfect for core drilling block to run pvc pipe through. Being a plumber, having to chip a hole through block to run pipes through underground is terrible. With this bit you simply drill a perfect hole, slide a sleeve through the block. Slide the pipe through the sleeve and you’re done. Great product. On hole #40 and still cuts great.

I used this in an attempt to bore 3 1/2" holes for a mini split AC unit. I hit rebar midway through the first hole. Helpful hint, turn off the hammering feature of your SDS Max tool if you hit rebar and try to slowly work your way through only drilling. I destroyed my first bit before I figured that out and had to buy a second to finish the hole. The second bit hit no rebar, but still had significant wear. I doubt I could have completed the second hole with the wear on the second bit, so I changed to a different bit. I bought a diamond dry core bit for less than half the price of this bit and it worked great. The diamond bit is slow because you cannot use the hammer feature and must only drill. However, it shows very little wear.

I returned this item too big for my drill

Bought this to bore a hole through an 18" thick stone house wall. With patience letting the drill do the work, it made a darn close to perfectly round hole relatively quickly. It also comes in a nice reusable plastic sleeve. Highly recommended.

I looked at one of these years ago in Canada and it was out of my price range. so when I bid a job to do a heat pump through an adobe wall I was expecting this to cost me much more.the core bit made quick work of the wall, concrete would be a little more time consuming and harder on the gear, but I still feel that it would be able to break through easily.I don't need to talk about the durability because it's Bosch and should last until my children use it anyway. but the price was great.

Super good

The diameter is NOT 2 1/4". It is 2 3/16". My guess is it is really metric. If your tolerance allows a smaller hole then buy it. A strong, well made tool but not as described. Returned to Amazon and ordered the 2 5/8" which turns out to be closer to 2 3/4". Again, assume they are both metric but the sellers approximate to the closest imperial measurement. I have seen them described in metric. Now I understand why.

Great product. Bosch makes great products. I have used this probably around 15 time. Through 8 inch concrete wall every time. Works as well as it did when it was new.

Excelente producto de muy alta calidad lo usare para meter tuveria eléctrica gruesa y para minisplit para sacar ductos y alambrado

This core drill cut through the old concrete foundation like butter! I expected to have to chisel out the central core. No, it made the 2" holes with just a pile of aggregate dust coming out.Worth every dollar!

I've had a rotary hammer for a long time, great for demo, but still been cutting holes in brick for vents with a grinder and chisel, because I figured these were too expensive for what you get. I was wrong... Way wrong... A... Didn't cost nearly as much as the guy at home Depot always quoted me (never buy specialty tools at depot)... B... This takes less than a minute to do what used to take a lot longer.Do glad I have the right tool for the job now... Even if it's not one I need that often...