The solution is based on the fact, that on the surface of the acetabulum there is a self-drilling thread, containing at least three independent teeth which advantageously have a concave shape of the cutting edge and a truncated pike, whereas the planes of their upper edges lie on a spherical surface. The apparatus includes a detector unit for detecting current, voltage and temperature of a battery cell; and soft computing unit for outputting a battery SOC estimation value of processing the current, the voltage and the temperature detected by the detector unit using a radial function based on a neural network algorithm. Female elements are formed integrally with an inner surface at each proximal end of said temple-contacting side members. This prevents the housing from cracking at the end surface extending around the opening when external stress is applied to the housing. The elongate body is configured to support the weight of the bicycles via contact with the rims of the bicycle wheels. This will lower the measured temperature dramatically in the thermometer which is in contact with the barrier, while the isolated thermometer will not have its measured temperature quickly lowered by the leak.