Contaprox Model I. 5522/13. Manufactured by Carl Zeiss. This is a close-up accessory for the Contax IIa/IIIa, produced post-war. It features a T-coated Tessar 50mm f3.5 lens.
The Contaprox consists of an adjustment head, intermediate ring, and focusing glass. It allows for closer focusing than the Contameter. To use, you attach a tripod to the tripod mount beneath the lens, precisely determine the distance to the subject using the focusing glass, then replace the focusing glass with the camera body for shooting.
This accessory exudes a sense of precision. It comes with an English instruction manual and a case.
There are minor scratches on the tripod mount, likely from previous use, and some scuff marks on the black paint, but overall, it shows little sign of use and has a clean appearance. In July 2024, the lens was cleaned, the aperture was serviced, and the focus was checked by a professional. The front element of the Tessar lens has some shallow cleaning marks, and the coating on the periphery of the rear element shows some wear, but this should have minimal impact on actual photography.
It would also make a fine addition to any collection.