CONTRACTOR shall at his own cost and expense obtain, maintain, and renew, or cause to be obtained, maintained, and renewed in full force and effect that necessary to cover his liabilities arising out of, and by virtue of the CONTRACT from insurers acceptable to COMPANY, throughout the duration of this CONTRACT and any extension thereof, the following insurances, it being understood that the risks may be covered by insurance policies in a different way than those indicated below provided that all such risks are properly covered