North Vietnam, 100 Years of International Red Cross, May 8th, 1963, Michel Nr. 255-257; Three stamps in the nominals 12 xu (two stamps) and 20 xu were issued. Perforation 11.0.
Here is a rather colorful franking sent to Theo Klewitz in 1976. It carries the entire Red Cross set and other North Vietnamese stamps for an overall franking of 1.3 Dong. Fulda arrival cancel on the reverse. Th letter was sent by Express Mail, so the overall franking makes sense.
Here is a letter in 1965 from Coa-Bang to Saint Louis in France. The letter carries one of the 20 xu Red Cross stamps among other North Vietnamese stamps for an overall postage of 74 xu. The standard letter rate to Western Europe was 50 xu, so this letter, that was sent by a public heath service center was heavier than the standard 20g letter.
Rare specimen/printed matter mailing from Xunhasaba in November of 1964 to a Western country (the address label has fallen off) featuring two of the 50D Southern Resistance stamps in Old Dong and two newer stamps in New Dong (including the 20xu Red Cross stamp). The old stamps had been devalued by 1,000:1 on Marc 1st, 1959, so they were only worth 10xu in 1964. The overall postage of this mixed currency franking amounted to 70xu.
Letter (ex Klewitz) that contains the entire perforated set plus some additional stamps on the front and reverse. The overall franking applied was 1.93 Dong which was in excess of the standard 20g registered letter rate to West Germany (1.1 Dong) however, Klewitz’ liaison in Vietnam was not known to waste any postage. So, the letter probably contained mint stamps and was hence heavier than the standard 20 grams.
Very rare letter (ex Klewitz) that features the souvenir sheet among other Vietnamese stamps (including the 12 xu Red Cross stamp). Souvenir sheets on postally used covers are very rare. The editor has only seen one other postally used letter with this souvenir sheet. Overall postage applied of 1.13 Dong. The required postage to West Germany was 1.1 (50 xu base letter rate, 60 xu registration fee).
Another letter sent from Yen-Bai to Paris, France. The letter carries the perforated 30 xu stamp of the Titow issue and other North Vietnamese stamps for an overall postage 74 xu. This was in excess of the standard letter rate of 50 xu, so the envelope must have been heavier the the standard 20 grams.
Registered letter sent to Klewitz in June of 1963 with one of the 20 xu stamps. The cover was franked with 72 xu which was in fact too little for a standard registered letter to West Germany (Tariff of 1.10 Dong), however, the sender duped the postal clerk into thinking the letter was actually routed to East Germany by writing “RDA” at the bottom of the address (which stood for East Germany). To that destination the required postage was only 12 xu for the letter and 60 xu for the international registration fee. To the clerk hence the letter looked like it was franked perfectly fine.
Rare registered express mail letter sent to Klewitz in October of 1969 featuring the entire perforated set. The overall postage amounted to 2.18 Dong which was in excess of the required postage for a standard registered express mail letter to West Germany (1.60 Dong). However, the letter may have been heavier than the standard 20 grams.
Registration Nr. 100760