3 Kr. perforated, as a single franking on cover, with single circle postmark "Mainz 26 5 70" to Wiesbaden, there undeliverable, appropriate violet boxed handstamp of one line as well label "sender adress from handwriting and seal not ascertainable" and red varnish seal "official opens" the upper Postal service direction in Darmstadt. Provenance collection Spalink, expertized Spalink BPP