The shaft is made of spring steel instead of hardened steel, so it flexes while drilling, allowing you to drill inside walls or between floors. A hole in the flute near the tip lets you pull wire through after holes are drilled. The end of the wire must be stripped prior to attaching it to the bit. Also known as bell hanger bits.

Use a hand guide (sold separately) to position flexible-shaft drill bits.

Use a ball guide (sold separately) to keep flexible-shaft drill bits centered between studs and drywall.