A device for disinfecting publicly-used equipment includes a plurality of reflective units disposed along the interior of each wall of the device. The covering includes a fabric form that is sized and configured to accommodate varying sizes of external fixation devices and uses readily engageablereleasable closure elements or fasteners to securely engage the covering about the fixator and the extremity. In the coating layer 2, blade-edge ridge 3, a range of at least 200 m from the rake face side boundary 6 of the same ridge toward the rake face side, and a range of at least 50 m from the flank side boundary 7 of the same ridge toward the flank side are formed to be smooth surfaces which substantially have surface roughness of 0.