Enables copper ion transmembrane transporter activity. Acts upstream of or within cellular copper ion homeostasis and copper ion import. Located in late endosome; plasma membrane; and recycling endosome. Is expressed in several structures, including adrenal gland; alimentary system; early embryo; nervous system; and nose. Orthologous to human SLC31A1 (solute carrier family 31 member 1). [provided by Alliance of Genome Resources, Apr 2022]