CHUCK & DRIVER ADAPTER Chuck Buddy. Every 3/8" power drill's best friend. It has a black plastic cone that will fit over a standard chuck with the drill bit for a pilot hole still chucked in place. On the end of the cone is a steel tube with a tip to hold a standard 1/4" screwdriver bit. Leave the driver in the buddy and slip it on and off the chuck to change quickly and easily between drilling pilot holes and driving wood screws. That's what friends are for.