4.—(1) No person shall supply any regulated vehicle which has four wheels and which is designed or intended for use by a person under the age of twelve (whether or not it is designed or intended for use also by older persons) if any of the requirements set out in the following paragraphs of this regulation is not satisfied in respect of the vehicle.
(2) The maximum speed at which the vehicle can travel when tested under the conditions set out in regulation 6 below shall be 15 miles per hour.
(3) The vehicle shall be fitted with a regulator which, when operated, ensures that the maximum speed at which the vehicle can travel when tested under the conditions set out in regulation 6 below is 10 miles per hour.
(4) The regulator required by paragraph (3) above shall be in operation.