I don't know anything about it. please check pictures. lenses look clear. focus knob run smoothly. Sold as seen untested. The Vintage Kern Aarau Swiss GK1 Theodolite Level is a rare and collectible engineering and surveying tool originating from Switzerland. Made of steel, this precision instrument is a valuable addition to any collection of scientific collectables. Presented in its original case, this theodolite level is not only a functional tool but also a piece of history that reflects the craftsmanship and quality of Swiss engineering.
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