This full sheet of 25 mint never hinged postage due stamps from 1912 represents the early Republic of China transitional issues, featuring a bold vertical red overprint in Sung-style Chinese characters on the blue 10 centimes design. Originally produced by Waterlow & Sons Ltd. in collaboration with the Customs Statistical Department in Shanghai, the stamp was printed using gravure and intended to bridge the Qing and Republican postal systems. The underlying design reads "POSTAGE DUE IMPERIAL POST" within an ornate oval frame, and the red overprint reads “中華民國” (Republic of China) to indicate its legitimacy under the new government. Perforation varies from 13½ to 15, and the sheet displays red plate number “434” with full selvage and intact corner margins, reflecting full production integrity. The issue is cataloged as Scott IM J31, Michel CN-IM P30, Stanley Gibbons CN-IM D213, Yvert CN-IM T23, and China Stamp Society CN-IM PD43. Exceptionally well preserved with bright color, crisp printing, and pristine gum, this full sheet exemplifies early republican postal reforms and their graphical legacy. Estimate "$450 – 550"