KÖNIGSHÜTTE, 10 Pfg orange-red, 20 Pfg blue vertical strip of three, 50 Pfg dark grey Steelworks and Dove of Peace 1920 on letter with advertising imprint (OHG Oberschlesische Handels-Gesellschaft, Königshütte) to Praha (= Prague) / Czechoslovakia, double-circle KÖNIGSHÜTTE 17 4 21 * (OBERSCHL) b (OS handbook No. 157.3), very decorative, rare cancel, upper left corner missing from 50 Pfg stamp, otherwise age and use marks typical of period