Mass. Gen. Laws ch. 231 § 85H
In any civil action for damages, failure to return any personal property acquired by a person under a lease or contract of hire or rental, other than a hired horse, carriage or other vehicle to which the provisions of section sixty-four of chapter two hundred and sixty-six apply, within thirty days after notice in writing of the termination of such lease or contract shall create a presumption that said person converted such property to his own use. Said notice of termination shall be delivered in hand by a sheriff or constable to the person who hired or rented such personal property as shown in the lease or contract of hire or rental, or shall be sent to him by registered mail, return receipt requested, with delivery restricted to the addressee only.
Mass. Gen. Laws ch. 231, § 85H