Rank Taylor Hobson 12" f4 British Anastigmat Aerial Prime Lens -Read, Fungus-
Here is a Taylor Hobson 12" f4 aerial lens. It is a well made British lens that was likely developed for military use. Included is an original yellow filter.
Note that this lens has some fungus on the edges of the rear element, which may soften images slightly when shooting in harsh conditions. All mechanical actions are smooth and the aperture is smooth.