International Letter-post Items Regulations

5 (1) A letter-post item shall not exceed

• (a) in the case of a card or postcard, 235 mm in length and 120 mm in width; and

• (b) in any other case, 380 mm in length, 270 mm in width and 20 mm in thickness.

(2) A card or postcard shall be made of cardboard or any other material that is commonly used in printing and shall weigh a minimum of 2 g so as to provide the stiffness necessary to withstand machine processing.