"Was installing a heated towel rail in place of the bathroom radiator and needed to drill a hole through the floor tiles to reposition the 15mm radiator pipe. The floor tiles are Category 5 hardness upon which masonry drills made no impression. This diamond core drill, however, did an excellent job. I followed the advice given in previous reviews, as well as the instructions supplied (kept the bit wet, dipped it into water every 10 seconds or so, cleared away the debris from the cutting site and let the drill cut at its own pace). The result was a perfectly smooth, accurate hole just the right size for 15mm pipe. Took about 20 minutes, but well worth the patience. The core drill is still good to drill more holes if required. Excellent value as well."
"I needed to drill four holes in thick porcelain tiles to run 15mm copper through. This drill bit drilled all four with no problems at all. I did use it wet, dribbling water onto the bit from a mug but I'm not sure if i really needed to do that! It certainly was good enough for me and saved me spending 6 times as much on another diamond bit from another manufacturer. Happy Driller."