B & A’s non-carbide Bell hanger
drill bits are specifically designed for small wire installation
applications. Telephone, security alarm, fire alarm, cable, network
installers, electricians, and other professionals all use these unique
drill bits to drill holes through walls, studs and other obstacles to
fish the small wire back through the drilled hole with ease. HDBH series
bits are designed for drilling through wood, plaster or drywall.