I drilled sixteen 3/4"-diameter holes 5" deep into the concrete floor of my shop in order to bolt down my 4-post lift. (That is way overkill, I know, but it makes me feel good.) First, because I knew nothing about concrete drilling, I tried a Makita hammer drill model HP2050 that uses straight-shank masonry bits. I had a really hard time drilling the holes because I couldn't keep the bits tight in the chuck, and then unit died after a couple of hours of use, so I got a refund from Home Depot and bought a Milwaukee model 5262-21 "SDS Plus" rotary hammer. This uses a so-called "SDS" bit that locks into the chuck "with authoritay", as they say on South Park. I found the easiest way to do it was to first drill a 3/8" starter hole and then the 3/4" final diameter. It was pretty easy with the Milwaukee "SDS Plus". I only used one masonry bit of both sizes. The lift is attached with standard 3/4" male wedge-type concrete anchors, and they all tightened up as much as I could twist them. I put shims under the column pads in order to plumb them in. I think I will also use the Milwaukee rotary hammer in the future to attach removable work fixtures to the floor with female wedge anchors while I am using them.