Carl Zeiss Jena Boxed Set of 5 Microscope Substage Lens Centring Holders + Extra

Carl Zeiss Jena Boxed Set of 5 Microscope Substage Lens Centring Holders + Extra. I bought this not know what it was, and have had fun researching it. There are no serial numbers and a couple of scribed details. I understand these are holders to centre the condenser lens of the substage of the Zeiss compound microscopes. Each holder has a thread to both sides and can be moved in the x-y-z axis. Each is slightly different in depth and has a dovetail to the rear, which fits a matched metal dovetailed rail in the box. The box itself is wooden and nicely made. There is no key, but hinges are sound. The areas that touch the holders are lined with blue velvet on of the lid holder is a match section. There are dinks to the timber inside and out but no detrimental damager to any of the items. One of the lid spacers is a replacement. There are 5 Zeiss holders (approx 27mm x 40mm) and 3 others of good quality - see photos.

Two are matched and similar size and the third is far larger (55mm width). There is also a small dovetail clamp (approx 32mm) with a screw mount beneath and lock ring. It was in the box so I have included it assuming it is something related.

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