I'm not able to test the mic properly as I don't have a dedicated carbon mic preamp/psu. It is being sold as is because I can't guarantee how well it will work with the correct preamp.
The last image is an cutsheet from a 1933 Bell Labs manual/catalog that describes the 600A.
The mic will be packed very carefully and shipped insured. Let me know if you have any questions and check out my other vintage pro audio listings.