The contracting authority needs to enter into a framework agreement for plastic and cast iron water meters. The competition will be held as a co-operation and three (3) contractual relationships will be established, one for Sandnes municipality, one for Sola municipality and one for Stavanger municipality. If a tenderer has tools and other material that is relevant for installations that use plastic and cast iron water and sewage materials, the Contracting Authority shall be able to trade such goods through this agreement, but it shall not prevent separate agreements from entering into for such products.