Netherlands East Indies. (Censored Diplomatic Mail). 1942. Air Mail envelope addressed to 'The Netherlands Legation, Washington, U.S.A.' headed 'Dienst/ Vru Van Port' with circular 'Department Van Ecomomische Zaken/ Batavia' in violet, bearing Netherlands Indies SG 399, 3g green, SG 438, 60c blue and SG 455, 1g + 1g grey (pair) tied by Batavia Centrum date stamp '16th Feb 42', hand-stamped 'Druwerk' in violet (Printed Matter) with framed 'Niet Door Censsuur Geopend/ 12' in carmine on face.
Very fine item sent at Air Mail Printed Matter rate with scarce censorship used on Diplomatic mail.
See Nico de Weijer's wonderful book on Netherlands Indies censor mail.