A universal jigwork holding fixture for precision manual reaming of valve bores within a transmission valve body, or other work piece is disclosed. The meter comprises a processing system for selecting one of the multiple types of power and defining the same as the selected type of power. The functional monitoring of said sign can be achieved with reasonable technical requirements in both the deactivated and activated state thereof. An outer edge of the external electrode is spaced away from the exposed portion by about 0. The bit retaining ring or the lower portion of the bushing has an internal diameter dimensioned to provide a close sliding fit with the outer diameter of the retaining shoulder on the stub shank.