(a) There may be a provision as follows:

“Other Insurance in this Insurer: If an accident or sickness or accident and sickness policy or policies previously issued by the insurer to the insured is in force concurrently herewith, making the aggregate indemnity for . . . . . . . . (insert type of coverage or coverages) in excess of $. . . . . . . (insert maximum limit of indemnity or indemnities) the excess insurance shall be void and all premiums paid for the excess shall be returned to the insured or to the estate of the insured.”

(b) In lieu of the provision in (a) of this section, there may be a provision as follows:

“Insurance effective at any one time on the insured under a like policy or policies in this insurer is limited to the one policy elected by the insured, the beneficiary or the estate of the insured, as the case may be, and the insurer will return all premiums paid for all other such policies.”