Netherlands East Indies. (Singapore). 1940. Air Mail envelope addressed to Driebergen bearing Netherlands Indies SG 405, 20c purple tied by Batavia Centrum date stamp '1st Feb 40', routed via Singapore with 'Passed by Censor' label tied by framed 'Passed By/ 46/ Censor' cachet in violet with circular '4' censor in violet on face. Very fine.
The single ring numeral censor appears to have been applied in transit at Singapore early 1940.