A rotary electric component includes a case for accommodating a rotary body having a cylindrical operation portion and for rotatably supporting the rotary body and a substrate having a rotation detecting means linked to the rotary body at a lower portion of the case. The cells are placed on the sweet spot on the head of the golf club. The controller routes incoming calls to a selected telephonic device within the residence, routes outgoing calls to a free external line servicing the residence, and routes calls within the residence from one telephonic device to another.