he master keys are stolen or if there are reasonable grounds to believe that the master keys may have been dupliNotwithstanding anything contained in this policy to the contrary if as a consequence of any event giving rise to a claim hereunder, tcated, the Insurer (s) will indemnify the Insured in respect of the cost of replacing locks and/or keys, provided that the total liability of the Insurer (s) during any one period of insurance for all such costs is limited to US$ 1,000.-