This is a really cool thermometer and flow rate unit. GPH for flow rate and C/F readings on the temp meter. It includes a thermometer well for verification of the temperature meter accuracy.
I believe it may have originally been used as a calibration or verification instrument for other Seabrook medical Systems products.
But it is a cool, no-batteries-required, analog / old school RELIABLE device. It'll still work after EMPs or Carrington-event level solar flares. :-)