A micro-pulsation metering fuel injection system, comprising a throttle body and at least one injection unit. A sheet connects the first fastener strip to the second fastener strip. The concave portion allows the club designer to make a club head having very thin portions while still maintaining the requisite structural integrity. The wireless controller driver controls the switching of the network mode. Specifically, fine particles discharged from a carbon cathode of an arc evaporation source by arc discharge are introduced into the coating, so that similarly amorphous, fine carbon particles are dispersed in the hydrogen-containing, amorphous carbon coating.