The RaceAir all-in-one weather station utilizes the same digital sensors as the RaceAir Pro but without the extra calculations and formulas. It features automatic air sampling with an internal fan to provide highly accurate results. Provides the weather data and calculated values to assist in E.T. prediction and engine tuning. The RaceAir unit can be upgraded to the RaceAir Pro level if your requirements change in the future. From it's main sensors you also get every weather variable you could want. The unit takes six AA batteries for long life.