#7 - 4.0mm single end German steel key, sized on the Swiss scale. New/old stock, original German made key. Fits Schatz 49 and 54 clocks, as well as others. 

Measure your winding arbor, or ask us for help to determine the right key size for your anniversary clock.

We only have a few of these left.  You will receive one of the pictured keys.  These may be used but will fit and are in good condition.