25 Fr. Red Cross block of four as correctly franked multiple franking on registered special delivery letter with special cancellation SAARBRÜCKEN IBASA 23. 4. 50 (2. strike on block of four from 29. 4. ) to Saarbrücken-Schönbach with arrival postmark on the UMMER over SAARBRÜCKEN 2 30. 4. 50, small margin traces, very scarce multiple franking, photo expertize Hoffmann BPP