I needed inexpensive V-bits for a small CNC machine to engrave on MDF, oak and acrylic. These fit the bill perfectly. While they are fragile, that is by design only and not through the fault of the product. They have a very small, extremely sharp point and if you push it into the material too quickly it will break. Like every other beat ever made. So this is a great kit for determining feed, speed and depth of cut because if you go too fast and break one they don't get too expensive. I broke 3 of the 30 degree router bits trying to get used to the new CNC router and each broke off about 0.5mm at the tip. No problem; They are still usable as I just sand them down to use as a flat bottomed engraving tip.