Do not hesitate to ask me with any questions that you may have. I have been a full time stamp & coin dealer for the past 45 years. Member of the ANA, ASDA, NGC and dealer member of the American Philatelic Society. Stamps only certificates from either APS, PSE or from the Philatelic Foundation are accepted, however "graded" certificates or "encased" items are not accepted.Proof of the inability to express an opinion is not grounds for return. We use the finest in secure packaging to better protect your items. Powered by SixBit's eCommerce Solution. The item "1929 Graf Zeppelin Switzerland South American Flight Cover Stuart Katz" is in sale since Monday, July 23, 2018. This item is in the category "Stamps\Europe\Switzerland". The seller is "stukatz-stamps" and is located in Hampton, New Hampshire. This item can be shipped worldwide.