Approx. Ø55,5mm, original metal case, floor labeled observation clock construction nhK, work number 216152, signed and numbered A. Lange & Söhne anchor chronometer movement with fine regulation, original dial, original light pointer, work starts when printing on the crown, but needs service. The clock is extremely rare. The name "Bauart nhK" stands as a camouflage code for the pilot watch (B-watches) produced by the manufacturer A. Lange & Söhne from Glashütte (Saxony) during the Second World War according to the instruction Fl. 23883. From the end of 1943, the letter code "nhK" was used to disguise the true origin (A. Lange & Söhne) and protect the manufacturer from targeted war damage or espionage.