Flavin adenine dinucleotide (FAD) transporter that facilitates export of flavin electron shuttles. Deletion of the gene results in a severe decrease in flavin export. Mutants lacking the gene have no defect in reduction of soluble Fe(III), but they are deficient in the rate of insoluble Fe(III) oxide reduction. Belongs to the multi antimicrobial extrusion (MATE) (TC 2.A.66.1) family.