Part of the ABC transporter complex ZnuABC involved in zinc import. Responsible for energy coupling to the transport system. ATP(in) + H2O(in) + Zn(2+)(out) = ADP(in) + H(+)(in) + phosphate(in) + Zn(2+)(in) The complex is composed of two ATP-binding proteins (ZnuC), two transmembrane proteins (ZnuB) and a solute-binding protein (ZnuA). Belongs to the ABC transporter superfamily. Zinc importer (TC 3.A.1.15.5) family.