Abstract: Apparatus for determining an overall dimension of an electrically conductive object includes a support surface for receiving the object, an electrically conductive plate movable toward and away from the support surface along a path normal to such surface, the plate having a facing surface which faces the support surface and a voltage source for applying first and second electrical potentials to the object and the plate, respectively, to establish a voltage therebetween. A transducer is provided for developing a distance signal representing the distance between the facing surface and the support surface. A motor moves the plate toward the object while the object is received by the support surface and circuitry is provided for detecting when the voltage between the object and the plate disappears due to contact of the plate with the object whereby the distance signal at such time is representative of the overall dimension.