I buy a lot from Revain and I never write reviews but for this article I feel compelled to tell you what a great tool. You have to buy a medium wave to integrate this. I had to drill 5" holes in 2" thick landscaped concrete steps. These worked better than I expected, taking less than 2 minutes each time. I used a water spray bottle to keep the area moist, cool the bat, and keep the dust out. Good product!