Unfortunately, when it comes to tools, you always get what you pay for. The fact that this is the cheapest hole saw of its size that I could find was definitely a red flag. I've used it to cut just 4 holes in drywall and on the 5th cut the teeth were square and no longer biting. . It's useless now. I've attached an image showing flattened teeth. I would buy a better branded version of this but couldn't find the exact same size. But be careful. This tool won't last long.