To safely and rapidly install wiring, and smoothly perform the motorization of existing non-motor-operated fittings and space-saving motor-operated fittings, by effectively utilizing a limited space while avoiding damage to the wiring, for example, caused by entanglement in a lifting body 6, against the background of a present situation wherein the number of switchboards for exclusive use with respective electric functional parts goes on increasing due to the promotion of installation of an obstacle sensor, the appearance of a remote-control unit, etc., in the generalization of a motorized type, in terms of a building shutter.

A current-carrying circuit element structure with a wholly or partially small thickness, which undergoes abrasion-resistant and electric leakage-resistant treatment, is installed on the inner surface of a bracket 2, so that an accident causing damage to the wiring can be prevented and so that labor for construction work and the space can be saved.