A crimping head for use with an impact wrench to crimp fittings onto a structure carrying the fitting, that includes a universal adaptor having a head, and a socket positioned in the head sized and shaped to receive a standard anvil of an impact wrench without further connection between the impact wrench and the crimping head. Next, the data object is examined to determine if a previously written data block is present that has an offset which is the same as one of the offset or the end of the read request. In some embodiments, the control circuit may be adapted to provide a vehicle unstable signal to activate a first occupant restraint system and a rollover detection signal to activate a second occupant restraint system. If, for example, the base-emitter voltage of the first bipolar transistor increases as a result of a higher supply voltage, the collector current of the third bipolar transistor is increased and thus the increase in the base current of the first bipolar transistor is reduced, thereby causing negative feedback. This invention compensates the chromatic aberrations of the objective lens with a chromatic aberration optical system or compensates for fluctuations in the wavelength by regulating the temperature of the semiconductor laser.