Windmesser or Anemometer
This Windmesser or Anemometer Air-speed Indicator or ASI was manufactured by Wilhelm Morell in Leipzig with a scale of 0-25 which corresponds to a maximum airspeed of 250 KPH or 155 MPH. This particular example has a serial number of 21329 or possibly 121329. The glass is stamped with a semi-transparent inspector's stamp of the Fliegertruppen symbol of a winged propellor and "P.u.M." The photo below shows an anemometer like this one attached to the starboard interplane strut of an Albatros D.Va of Jasta 16b. Note that this object is in poor condition as the wind cups are sagging and one has been re-attached.