Using interchangeable probes this versatile meter reads airspeed, temperature, RH and light. the user can order probes for only the parameters currently required and add additional probes in the future. Intelligent probes electronically retain calibration information. No recalbiration is required when changing probes. The display simultaneously reads temperature in user selectable °C or °F and all measurements are automatically temperature compensated. An RS-232 port enables communication with a computer. It also features auto power off, hold and min-max. Fold out easel back and a tripod screw. The unit includes a 9V battery and a hard shell foam lined carrying case with room for one or two probes. Dim: 7.75" x 2.5" x 1".