The included storage case keep drill bits organized by size ( 2.8mm-4mm), ensuring quick access and protecting hard steel tipped cutting edges during transport or job site use Crafted with hardmetal alloy, this countersink drill bits set ensures high precisions woodworking with sharpened steel for fast, clean holes in wood,, and PVC Ideal for woodworking professionals and DIYer enthusiasts seeking great tool for cabinetry, furniture assembly, or craft projects requiring flush screw installations Featuring integrated ball bearing and depth stop collars, the drill bits wood splintering while maintaining consistent countersinking depth for professional result Perfect for workshop tasks like installing hinges on wooden doors, assembling plywood structures, or crafting decorative wooden items needing concealed fasteners, Manufacturer: GinMimi