Floyd Bennet Field was first constructed as a commercial airport from 1928 to 1931. This cover located between two of the first hangars constructed, could well be from this period.
Although the design of the cover is very similar to the design (#1049) from the profligate Campbell Foundry, it has a number of differences, both in the proportions of the rings and the extent of the 'spokes". More importantly this cover was hinged, note the slightly eccentric indent in the cover rim and to the squared off pry hole opposite. There were numerous agencies and contractors involved in building the airport, so no universal design standards were enforced.
This is the only known example of this particular variety.