A composite having a poly coupling agent, a filler, and a biocompatible, biodegradable polymer matrix is disclosed. The switching device is mounted in series on a local electrically powered circuit on which are also mounted in series a load and an electronic thermostat. The telephony logic is also capable of dynamically switching between the use of the first and second speakersmicrophones andor the first and second network interfaces in response to detecting engagement or disengagement of the docking station during a voice call. The locking means comprises a hole formed in the rotary shaft, an eccentric cam to be rotated by the chuck cover, and a lock pin which is moved by the eccentric cam so as to be inserted into the hole of the rotary shaft when the chuck is not covered with the chuck cover.