China. (Trans - Pacific Mail). 1940. Registered Air Mail envelope addressed to Amsterdam, Netherlands bearing SG 403, $1 brown and grey, SG 415, 10c purple and SG 456, 10c on 20c blue (2) tied by Shanghai date stamp '31st Dec 39' with matching registration label, endorsed 'via U,S,A,' with Amsterdam receiver '19/1/40' on face.