Kern & Sohne Clock Company was formed in 1937 by Karl Kern and his sons. The company produced mainspring-driven 400-day "anniversary clocks" up to 1985. The 400-day clocks manufactured by various companies have similarities which, at first impression, can be difficult to identify if the brand is not noted on the dial. Since 400-day clocks are shielded with a clear glass dome, identifying the Kern & Sohne clock requires no special skills or tools.
Check the dial. This is the most expedient method of identifying a Kern & Sohne clock. On some clocks, only the name "Kern" may be present on the dial.
Check the back plate of the clock for further verification.
Examine the lower right-hand side of the back plate for the name "Kern & Sohne" engraved into the brass.
Look at the lower left side of the back plate for a conspicuous circle with the letters "KS" within it. Immediately below the circle, check for the word "Germany."
- Circles that surround the letters "KS" may have incremented lines around the circumference or a double-ring circle with lines between the two rings.
- A clock purchased for parts or restoration that has no dial can be identified by markings found on the back plate.
- Most Kern & Sohne movements have a version of the KS logo on the back plate, unless the plate is marked with "K.u.S" followed by the movement reference number.