ADI PRO's assortment of drill bits allows you to select the right drill bit for the job. With options designed to drill through metal, wood and masonry walls with lengths from 4" to 72" and bit diameters of ¼", 3/8"and ½" you can rely on ADI PRO drill bits for installing computer, security, phone, and cable small wire systems. The3/8" x 18" 0E-3818HSFBT High Speed Flex Drill Bit drills through metal and wood with ease.