Teledyne Mixchek helium oxygen battery powered analyzer

I am selling this for a friend. It is a teledyne mixchek battery powered analyzer for helium and oxygen. I?m sure the sensor or sensors will need replaced. I know know nothing about this unit. It looks very unused. I?ll try to post a few pics. I do know they were expensive when they first came out. I also found and printed a manual from on line. Info on this unit appreciated. Can?t figure out how to post pics. Message me with phone number or email and I?ll forward.

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