it's amazing the things I run across - I found a datum attachment for a Taylor Hobson Talysurf profile meter and surface measuring device - if I understand the info on the company's site, this thing reads down into nanometers - and what I found was an accessory, not the whole thing - but if any of you folks work with such a device, this accessory must be useful and I'll bet it goes cheaply.
here's the link
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