?High Quality Material??Made from M35 high speed steel with cobalt for added durability, the Yougfin jobber twist bits are friction and heat resistant ?Dual Flutes?:Drill bits are rotary cutting tools that have two cutting edges and two flutes which are grooves formed in the body to provide cutting lips, to permit the removal of chips and to allow coolant or cutting fluid to reach the cutting action ?135 Split Point??These bits have a small point angle of 135 and require less pressure when centering in the material. The point starts drilling at contact, reducing friction, pressure, and heat. The larger the point angle, the higher the contact pressure and the centering in the material requires more pressure ?Product Feature?: Twist drills are indicated in sizes. Assortment comes with a combined 21 sizes added?1/16", 5/64", 3/32", 7/64", 1/8", 9/64", 5/32", 11/64", 3/16", 13/64", 7/32", 15/64", 1/4", 17/64", 9/32", 19/64", 5/16", 21/64", 11/32", 23/64", 3/8" ?Application Tip??Yougfin Jobber Drill Bit are ideal for sheet metal working and are suitable for cutting non-ferrous metals, plastic, wood board, etc. ***Tip***?Please keep the bit perpendicular to the material during operation to prevent it from breakage. If you have any questions about Yougfin products, please feel free to contact us B0B58BVSBP