This is a Britsh Meteorological Office anemometer dial manufactured by R.W. Munro, London. The standard recording range for these  instruments is zero to 90 knots or 100 miles per hour and would have been issued by the Met Office to RAF and Coastguard Stations as well as important observation sites. However, this particular example is quite rare as the dial displays double the range, zero to 180 knots (or in excess or 200 mph!). This would have been used in highly exposed areas, generally coastal, elevated sites or British territories abroad where extreme weather conditions such as hurricanes or typhoons can be experienced. This instrument is sold on its own with an extract from the Munro trade catalogue and would make a lovely display piece. 
Note! The 3-cup anemometer head is not included although I have a couple of these available which would require servicing and could be sold separately if required.
132mm diameter overall x 112mm deep