Compass, Magnetic, FL23233, Luftwaffe
Here is a WW2-era German Magnetic Compass FI.23233, made by Ludolph, as used in aircraft of the Luftwaffe.
This version has a gradient on the lens which indicates degree of climb or decent from +/- 20 degrees as the compass card tilts with the change in aircraft attitude.
The fluid has turned slightly brown, but it remains an exceptional specimen. The upper mount remains attached. According to Aircraft-Cockpits.com, this compass was used in aircraft Ar79, He72, Ju52, Klem KL35, Bf108D, Ar234B-1, Bu181, DFS 230, and Fi156.