Airspeed Indicator, 900 km/h, Luftwaffe Fahrtmesser Fl.22234 Lily Bomber thus following the airspeed index

thus following the airspeed index on the inner scale

used by bombardiers and technicians to check the proper operation of the Norden Bombsight

The pointer is calibrated by turning the screw in the lower left corner

The bracket has one spirit level to ensure that the gunsight body is level perpendicular to the line of flight

Nakajima B5N Torpedo Bomber Type 97 aka "Kate"

Airspeed Indicator, 900 km/h, Luftwaffe Fahrtmesser Fl.22234 Lily Bomber thus following the airspeed indexHere is a WW2 era German Airspeed Indicator FI. 22234, with a maximum airspeed of ~900 km h. As the airspeed increases, rotating the pointer clockwise from the 6 o'clock position, it rotates 360deg past 0 once 800 km h is exceeded, thus following the airspeed index on the inner scale, up to ~900 km h. According to AircraftCockpits. com, this was used in aircraft such as Do335, Fi103, FW190A7 9, Ta152, Go229, He162, He219, Ju388, Bf109G, Fi103, and