Section 4
Section 4. Whenever several bidders shall participate in the bidding for supplying articles, materials, and equipment for any dependencies mentioned in section one of this Act for public use, public buildings, or public works, the award shall be made to the domestic entity making the lowest bid, provided it is not more than fifteen per centum in excess of the lowest bid made by a bidder other than a domestic entity, as the term "domestic entity" is defined in section two of this Act.