Professional Sharpening: Designed for 313 mm drill bits, VEVOR MR-13D drill bit sharpener with 11 elastic collets excels at sharpening the point angle, lip relief angle, and front cutting edge, quickly restoring your bits to optimal sharpness and precision Multiple Adjustments: The drill bits grinder sharpener offers flexible adjustment for the lip relief angle, front cutting lip, and 95°135° adjustable drill point angle, precisely matching various bit styles and drilling needs, ensuring smoother and more accurate sharpening results Efficient Grinding Wheel: The CBN grinding wheel (pre-installed) is designed for high-speed steel materials, greatly improving grinding precision and efficiency