These drill bits meet National Aerospace Specification (NAS) 907 Type B. They have a TiCN coating that protects them from wear and is harder and more wear-resistant than a TiN coating.,These high-speed steel jobber-length drill bits meet National Aerospace Specifications (NAS) for drill bits used in aircraft production and repair. These drill bits do not have coolant holes, so a separate hose is required to bring coolant to the bits tip if it is needed. The bits are made from high-speed steel. They 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. These bits have spiral flutes that evacuate chips as the bits drill into a workpiece. 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.