Perfect for drilling precise square holes in hardwood, softwood, or composite materials when paired with mortising machines or drill press attachments The 7Pcs Square Hole Mortise chisels Drill Bit Set features accuracy ground steel construction and 7 size options ( 1 / 4in to 5 / 8in) for creating clean, square holes in woodworking projects with unmatched durability Ideal for professional carpenters, furniture makers, and craft enthusiasts requiring efficient mortising tools for cabinetry, door locks, or joinery work This complete square drill bits set combines industrial materials with exacting dimensional accuracy ( 6.4mm 16mm sizes) for seamless compatibility with standard woodworking power tools Heat treated carbon steel bits with piercing chisels edges ensures reduced friction and extended tool life, while the included storage box keeps your woodworking hole set organized and portable, Manufacturer: ERRORY