Thermic Fluids Corporation offers Highly Stable Long Lasting Silicone Fluid. Thermic Fluids also offers ranges of synthetic heat transfer fluids like Dowtherm, Syltherm, Dowcal, Dowfrost etc manufactured and marketed by The Dow Chemical Company, USA. The Highly Stable Long Lasting Silicone Fluid, also known as Syltherm 800, has an operating temperature range of -40 Degree C to 400 Degree C. The Highly Stable Long Lasting Silicone Fluid can remain in service for 10 years or more, even when operated at the upper end of its recommended operating range.