A reciprocating compressor, being small-sized and compact, for compressing hydrogen gas to be used in a fuel-cell car, has a crankshaft, to which an end of a connecting rod is connected. A service-request-compatible apparatus processes a received network-service request, and provides a service. A sacrificial layer having a height is deposited on the first metal layer. , locking and unlocking of the car door. The drive member is releasably engaged with the retainer, allowing the wrench to be used with various types of drive members for driving various types of fasteners.