The Vintage Pyrotest Pyrometer West Instrument Corporation Model No 9B is a collectible piece from 1964, manufactured in the United States. This potentiometer pyrometer is a unique and rare item that would be a valuable addition to any collection of scientific and medical instruments. With its optical design and historical significance, this pyrometer is sure to be a conversation starter for collectors and enthusiasts alike. The serial number is 64020412. This has manual, letter regarding models and brochure from the manufacturer.  This is for calibrating all types of actuated temperature instruments. I am selling as is and no returns this is heavy.