The hardest and most wear-resistant bits, the flutes clear chips and improve coolant flow. They prevent clogs and dissipate heat that can damage the bit and the hole. Carbide bits stay sharp at high temperatures and faster speeds for the best performance on hard and difficult-to-machine materials. They last 10 to 20 times longer than cobalt steel. Carbide can be brittle, however, so these bits require a rigid machine tool holder to prevent breakage and should not be used in hand drilling applications.