Companies may bring goods into Saudi Arabia for a temporary duration for promotional purposes provided they include both an invoice with the value of the goods endorsed by the local chamber of commerce and a certificate of origin.  Prior permission to import samples must be obtained from the director of customs in Riyadh.  The request for permission to import must be accompanied by samples, prices, and catalogs.  Commercial samples are subject to the payment of customs duty and surcharge either by a deposit equal to the duty at the time of import or by a bank guarantee.  The invoice should state that the goods are being imported for exhibition purposes only and that they will be re-exported when the exhibition is concluded. This deposit is refundable when the trade show is over and upon showing a document that the owner of the equipment officially participated in a trade show.  A refund is made if the goods are re-exported within 12 months.  If the samples are sold, neither the deposit nor the guarantee will be refunded.  A nonrefundable duty is levied on imports of samples of jewelry and watches.  Factory advertising materials, excluding printed and illustrated calendars, imported for display may be imported duty-free if the applicable duty is minimal.  All catalogs and brochures for which no charge is made may enter duty-free.