Trial Lens Adapter Reducer to Mount 32mm Trial Lenses in 38mm American Optical Trial Frame

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Trial Lens Adapter to Mount early 32mm Trial Lenses in 38mm early model American Optical Trial Frames and similar models that have a pin-style lens holder opposite the spring holders. Will hold two 32mm trial lenses.This adapter works in both my 1920 and 1940 era American Optical trial frames. It should work in similar early trial frames by AO, Bausch & Lomb, STOCO and others, with some remixing. Historical note: modern trial lenses are generally based on a 38mm fit format. Manufacturers, such as Geneva Optical and B&L offered trial lenses in both 1 ¼” and 1 ½” sizes, at least through the 1920’s. These would have been referred to as 32mm and 38mm outside the US. Many of the old smaller 32mm lens sets are out there, however the early trial frames were not robust and, when found, are usually broken, over-priced, or both.