48 therefore there are caused differences to the pressing force of the tips 36 a of the probes 36 i e the needle pressures of the probes 36 of the electrical connecting apparatus 10 in correspondence to differences of 0 6 mm at a maximum in the electrical connecting apparatus 10 according to the present invention in spite of dispersion due to production error in the plate thickness dimension l 4 of the reinforcing plate 20 the number of the spacer plates 48 selected to correspond to the plate thickness of the reinforcing plate 20 is selected so that the distance l 3 from the mounting surface 16 a of the card holder 16 to imaginary plate p where the tips of the probes 36 may be aligned can be kept at a proper value therefore in the electrical connecting apparatus 10 according to the present invention where each spacer plate 48 has a thickness dimension for example of 100 u03bcm six spacer plates 48 at a maximum are laminated between the reinforcing plate 20 and the circuit board 18 and by selecting the number of proper spacer plates 48 to be inserted thereby enabling to conduct an electrical inspection of the semiconductor wafer 14 with substantial difference in needle pressure kept almost at zero by the insertion of the spacer plates 48 the distance between the reinforcing plate 20 and the circuit board 18 is increased by the total thickness dimension corresponding to the number of the spacer plates 48 according to the increase in distance however spacer members 54 for example can be replaced with those having the proper length dimension.