The Water Triple Point is the most important fixed point, the only point common to the ITS-90 and the Thermodynamic Temperature Scale. It is an essential reference point for every temperature laboratory. The Jarrett-Isotech cells are the best standard, all cells are not the same, accept no inferior device.

Total Confidence – The Internationally Proven Cells The Jarrett-Isotech cells have been in production since 1958. A 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.

*“ Reproducibility of Some Triple Point of Water Cells”By George T. Furukawa and William R. Bigge. Temperature - Its Measurement & Control in Science & Industry Vol. 5 1982. ** Final Report on CCT-K7: Key comparison of water triple point cells. M Stock et al 2006 Metrologia 43 03001

Model Types	Performance
Premium Water Triple Point Cells - Borosilicate Glass	These Premium Cells can be calibrated to an uncertainty of +/- 0.000070°C (0.07mK) A11-50-270*, A13-50-270*, B11-50-270, B11-65-270*, B13-65-270, B16-65-270 *also available in Quartz Glass.
Reproductilibity	The equilibrium temperature of a cell will repeat to within ±0.000,02°C of the mean equilibrium temperature.
Stability	After equilibrium is reached, the mean temperature of the inner melt of an ice mantle will remain constant to within ±0.000,01°C for as long as the mantle can be preserved (up to 90 days in some instances).
Further Laboratory Water Triple Point Cells	These Cells have shorter immersion depth and can be calibrated to an uncertainty of ±0.000100°C (0.1mK). B12-40-210, B12-46-210.
Life	Cells made from Borosilicate Glass may drift lower in temperature by up to 0.1mK after 10 to 20 years. Cells made from Quartz Glass are expected to last 10 times longer.
Accuracy	The equilibrium of temperature of the Jarrett-Isotech Triple Point of Water Cell is within ±20μK of the 2005 definition as described in CCT/05-07/rev(2). Isotopic Analysis can be provided to give the exact composition within ±3μK.
Slim Water Triple Point Cells	B8-30-130 This small cell fits into portable Dry Block Calibrators for use outside of the calibration industry. It can be calibrated to ±0.0005°C (0.5mK).