Belgium. British WWI-era military mail in Europe: 23 DE 1918 OAS honor envelope (type W299-M1950) from FPO 1Z (96 Brigade of 32nd Division, NAMUR area) to MANCHESTER, tied by 1.Z postmark; although signed & not franked for special postal treatment, opened & inspected by military censor - this unusual, especially as post-war; possibly left unsealed as most of gum still on back-flap.

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