Zinc endopeptidase with endothelin-3-converting enzyme activity. Cleaves EDN1, EDN2 and EDN3 (By similarity). Binds 1 zinc ion per subunit. Heterodimer with XK; disulfide-linked. Spans the erythrocyte membrane, and is attached to the underlying cytoskeleton. Highly expressed in spleen. Weaker expression in testis and heart. N-glycosylated. Belongs to the peptidase M13 family.