PROFESSIONAL COUNTERSINK DRILL BIT SET Includes three countersink bits in sizes #6, #8, and #10, designed for up to 3/8 (10mm) screw heads. Crafted with premium High-Speed Steel M2 (6542 grade) tapered drill bits for precise, clean cuts. The set also includes a stop collar and hex wrench for adjustable depth control. ADJUSTABLE COUNTERSINK DEPTH The adjustable stop collar allows for controlled and consistent counterbore depth, while the adjustable cutters make it easy to fit different screw sizes, ensuring a flush, professional finish on all woodworking projects. QUICK-CHANGE COMPATIBILITY Built with a universal 1/4 hex shank, making it compatible with all 1/4 quick-change chucks for fast and efficient bit swaps. DURABLE & HIGH-PERFORMANCE MATERIALS Manufactured under JNB Pro s strict quality standards, featuring High-Speed Steel M2 (6542 grade) drill bits for long-lasting sharpness and smooth drilling. The Carbon Steel #45 countersink cutters are coated with Black Oxide for enhanced corrosion resistance and durability. PERFECT FOR PROFESSIONALS & DIYers Designed for cabinet makers, woodworkers, and carpenters who need clean and precise countersinking for hardwood, softwood, MDF, and plywood.