Three types of original Japanese National Railways horizontal envelopes from the era (12 large, 20 medium, 30 small) - Not standard-sized envelopes, but rare custom sizes and designs ordered by JNR. - Feature the notation "紙xx" (Kami xx) for management numbers of paper used in government offices, schools, and public corporations during the Showa 40s-50s (1965-1974). - Include notations of suppliers such as "高春堂" (Kōshundō), which supplied to government offices. - Show notations like "(53.5. 高春堂)" (53.5. Kōshundō) indicating May 1978. ● 紙47 (54.5 Kōshundō supplied) 12 sheets Approx. 267mm × 190mm ● 紙48 (54.5 Tōyōkan supplied) 20 sheets Approx. 270mm × 125mm ● 紙49 (53.5 Kōshundō supplied) 30 sheets Approx. 190mm × 125mm Slightly larger than the current Western-style No. 2 envelope (162x114), large enough to fit foreign postcards. May have been unusual for the time. - There is paper yellowing due to age. Some may have folds or stains.