Requirements are Dry Ice, Special Box and a overnight 24 hour service. Dry Ice only lasts 24 ours without melting no matter the amount of Ice it's chemical compounds only lasts for a predetermined time. To learn more about Dry Ice please read this article from Wikipedia. Before you can ship a cold butter cream or gourmet cake you need the Dry Ice. Local Ice companies can provide  you with Ice. Approximately you will need 5 pounds of dry ice for a regular 10 inch cake or more for a rectangular 1/4 sheet cake.