Installation of parts and materials supplied by the ordering party. 1.4.1 The contractor guarantees the execution of the contractual services. He is not liable for the quality and suitability of the parts and materials supplied by the ordering party. If the contractor has any doubts as to the quality and suitability of such parts and materials, he has to inform the ordering party without delay. If such doubts or misgivings are not taken into account, the contractor, in serious cases, has the right to refuse the execution of the respective work.
