The ThermoStat™ 900 is a high flow, in-line, microwave, blood and fluid warmer. “In-Line” means that fluids are heated at they flow through the IV line The T900™ is factory set to heat blood or fluids to 40°C in five seconds, regardless of the flow rate or temperature of the incoming fluid. 40°C is the actual outlet temperature of the fluid, not the temperature of a water bath or metal plate which must then by conduction, heat the fluid line (tube) and then the fluid as it passes through the tube. The core technology of the T900™ consists of three radiometers and a 900 watt magnetron connected by a patented feedback loop. The first radiometer senses the temperature of the incoming fluid. The second senses the flow rate of the fluid. The third senses the outlet temperature of the fluid as it exits the heating chamber. Given the three measurements, the machine “knows” how much power to put into the heating chamber to keep the actual outlet temperature at a constant 40°C regardless of any change in incoming temperature or flow rate. The temperature and flow rate is non-invasively sampled at 60 times per second (microwaves travel at the speed of light).