MaterialsPurchase of MaterialsWhere specifically required the sub-contractor should produce evidence of its specification ie. Material Test Certificate, which should be issued to the Company upon the completion of the contract.The sub-contractor shall retain proof of origin of all materials used in the manufacture of the Company’s products by means of record of purchase or the like ( for a minimum period of 5 years), clearly identifying the materials used and upon which date.It is required that all material covered by this specification are marked with its cast or identification number so that all material used in manufacturing the Company’s products is traceable.