it shall be a requirement of this policy that the sum insured in equal to the cost of replacement of the insured items by new items of the same kind and capacity,which means their cost of replacement including,eg,fright,customs duties and dues, if any and cost of erection. if the sum insured is less than the amount required to be insured the insurer shall pay only in such proportion as the as the sum insured be are to the amount required to be insured. Every item if more than one shall be subject to this condition separately.