Divalent metal cation transporter which exports Zn(2+), Cd(2+) and possibly Fe(2+). May be involved in zinc and iron detoxification by efflux. H(+)(out) + Zn(2+)(in) = H(+)(in) + Zn(2+)(out) Cd(2+)(in) + H(+)(out) = Cd(2+)(out) + H(+)(in) Fe(2+)(in) + H(+)(out) = Fe(2+)(out) + H(+)(in) Homodimer. Belongs to the cation diffusion facilitator (CDF) transporter (TC 2.A.4) family. FieF subfamily.