South West Africa 1916 WWI POW PRISONER OF WAR CAMP OKANJANDE Commandant Cover

Stampless cover, endorsed “Prisoner of War!”, postmarked with altered German “ - WINDHOEK / - POST / 4 PM/ 23.8.16” bahnpost railway cancel, struck with mostly clear crown oval “Commandant P of W Camp / Protectorate S.W. Africa  / OFFICIAL FREE”, to the Schutztruppe in Windhoek, boxed rose censorship h/s at top, camp return address in manuscript on reverse, a fresh and clean cover.