These bits are designed for finish jobs on contoured edges such as plywood tops, stair treads, window sills etc. This carbide tipped bit is specifically designed and manufactured for the high quality demanded by woodworking industrial applications. The cutting edges of this router bit are made from high industrial grade micrograin carbide tips brazed onto a heat-treated high-carbon steel body thus leading to exceptional hardness and rigidity. Its cutting edges are radially relieved for a strong smooth cut in addition to avoiding rubbing and burning. It is precision ground, hardened, and tempered in order to stand up to a variety of materials. It is also equipped with wide open gullets for easy disposal of wood chips. It is suited for softwoods, hardwoods, chipboard, plywood and etc. Note : In order to avoid vibration and for maximum cutting quality, always choose a router bit with the shortest cutting edge and the shortest overall length available that is able to fit your project application. Excessive overall length may cause tool damage. In case a bit doesn't come with a speed chart. You may try the following suggestion. This is merely a guideline to start, result likely varies due to the varieties of edge and material hardness: Run 24,000 rpm maximum for 1" overall diameter router bits; Run 18,000 rpm maximum for 1-1/4" overall diameter router bits; Run 16,000 rpm maximum for 2-1/4" to 2-1/2" overall diameter router bits; Run 12,000 rpm maximum for 3" to 3-1/2" overall diameter router bits;