Failed to load media. I use these bits to drill concrete blocks for my chicken coop. It can cut concrete easily. It was also able to drill through my pressure machined joist as I didn't want to switch drill bits back and forth. That has accelerated my work enormously. The bits are not marked so you will need to measure them to fit your head. This is the hole size as it is the widest part. I placed the anchor bolts just behind the drill head and if you can see the edges of the bolts you need a larger drill bit. This allows the hole to be slightly larger than the drill so you don't have to hammer it in.