The ATC series offers a wide temperature calibration range (-90 to 650oC) and improved stability (+ 0.01oC for most models) for marine calibration. It utilizes innovative dual-zone heating technology for precision calibration of sensors. Independent heating control allows the lower zone to ensure optimum heat dissipation throughout the entire calibration zone, while the upper zone compensates for heat loss from the sensor-under-test and the open top. This design also eliminates the need for insulation of the sensors-under-test and allows calibration of liquid-filled and other mechanical sensors. Major Features: 12-month accuracy to В±0.04oC / 0.07oF, Temperature range -90o to 650oC / -130o to 1202oF, Stability to В±0.01В°C / 0.018В°F, 14 different models, MVI stability circuitry, 100% automatic calibration, RS232 interface and JOFRACAL calibration software, Input for external reference sensor and sensor-under-test, Timesaving auto-stepping and temperature switch test functions, Interchangeable inserts including multi-hole designs, Active dual-zone