On the certificate should be sign and stamp.
If a control document is not produced when otherwise required, a certificate of shipment or an authority to load endorsement can be given on an officially stamped sheet suitably as a complete to identify the goods.
You should not, give more than one certificate or endorsement for the same goods unless they are subject to more than one claim to drawback, relief or refund in which case a suitable cross reference should be made on all forms on which a certificate or endorsement is given.
For shipment of dangerous goods it is critical to identify goods by proper name, comply with packaging and labeling requirements, which vary depending upon the type of product shipper and the country shipped to.
The exporter is responsible for accuracy of the form and ensuring that requirements related to packaging, marking, and other required information have been met.