Jarrett-Isotech cells have been in production since 1958. An independent comparison in 1981 showed the first cell to be within 0.000006°C of the reference cell. The most recent international study organized by BIPM consistently shows labs using both recent and older Jarrett-Isotech cells tightly grouped, tens of μK around the BIPM reference value. International comparisons prove the quality of the Jarrett-Isotech cells and are unique in the number and history of comprehensive evaluations.
The B8-30-130 fits into portable Dry Block Calibrators for use outside of the calibration laboratory. It can be calibrated to ۪.0005°C (0.5mK).