Bulgaria C 75, MNH Michel 1027. Air Post 1957. Civil Aviation, 10th Ann. Passenger plane. Block of 4 - buy 4 stamps. For domestic purchases up to $60.00 first class mail will be used; purchases above $60.00 require mail with tracking number (buyer pays the mail fee). For international purchases up to $60.00 first class international airmail will be used; purchases over $60.00 require mail with tracking number (registered mail, buyer pays the $23.00 or $26.00 for oversize item). Warning for the buyers from Eastern European countries, Russia, China, Middle East, South Asia, Latin America, Africa exclude RSA, and the buyers with eBay ID less 100: the purchases over $30.00 require expedited mail.