Wound closure apparatus is provided having a force-transmitting surface operable to be placed in a proximal, external, wound-closing position on a patient, together with a force-exerting assembly operable to exert a wound-closing pressure against the patient’s tissue. A holder for an inductive component includes the carrier device and an electrical isolation device. For allowing two or more light bodies to be synchronously controlled, the switching signal indicative of the counted switching number is substantially simultaneously transmitted to the counting and control unit of each of the light bodies without passing through the bridge current rectifying unit.