4d blue GV postal stationery registered envelope of South Africa with 'Zuidwest Afrika' overprint in red (H&G C8) used with added pair 1923 1d rose red 'GV Head' issue with 'ZUIDWEST AFRIKA' overprint, setting VI (SG 30) tied by KOLMANNSKOP 'German' type cds's dated 17 12 1925 with boxed 'KOLMANKOP' registration marking in violet alongside. Addressed to WINDHOEK with 'German' style arrival cds on reverse. Scarce.