I bought this drill bit to drill through some ceramic tile that was already installed in my shower. Each hole lasted several minutes. I stopped about every 15 seconds to wet the bat and tiles to prevent excessive heat build-up. I probably didn't have to stop as often, but I'd rather be overly careful than risk breaking the tile. I have now safely installed the curved shower curtain rod and my wife is delighted. If I ever need to drill tile again I will definitely buy one of these drill bits. I'm keeping my fingers crossed that I'll never have to drill tiles again.