The TiN coating on these drill bits protects them from wear and heat when drilling steel, stainless steel, and aluminum. Parabolic-flute drill bits have wide, deep flutes that improve chip flow and heat dissipation, which means feed rates do not need to be reduced as the drills move deeper into the workpiece. These bits have a straight shank that installs into a drill chuck or similar toolholder.,Non-coolant-through high-speed steel jobber-length drill bits do not have coolant holes, so a separate hose is required to bring coolant to the bits tip if it is needed. High-speed steel drill bits provide more flexibility and absorb more shock and vibration than cobalt, powdered-metal, and carbide drill bits, making them suitable for use in manual drilling machines and handheld power tools. They may leave a rough finish on the hole. Jobber-length drill bits are the most commonly used drill-bit length. They provide a good balance of strength and accuracy when drilling into a range of materials.