An extension shaft for holding a tool for rotary motion of the tool includes a first end adapted to cooperate with a chuck of a handheld instrument and a second end including a tool holder for holding the tool for rotary driven motion thereof. The tool holder includes a base portion operatively connected to the extension shaft and a swivel portion capable of holding the tool. The swivel portion is pivotly coupled to the base portion through a pivot assembly, wherein the tool is capable of being rotated about an angle with respect to an axis of the chuck through rotation of the extension shaft in response to rotation of the chuck.