IF you're looking for durable, high-quality diamond mandrels, these are a great option .As my tests showed, they cut smoothly through a variety of materials, including metal, wood and plastic. Plus, the circular shape makes it easier to achieve precise cuts. The only downside is that they are a bit pricier than some other options on the market. Overall, I highly recommend these mandrels for any DIY enthusiast or professional power tool user..See full review