Resolution 0.1 W mˉ² Calibration Factor Custom for each sensor and stored in firmware Calibration Uncertainty ± 10 % Measurement Repeatability Less than 1 % Long-term Drift (Non-stability) Less than 3 % per year Non-linearity Less than 1 % (up to 300 µmol mˉ² sˉ¹) Response Time Software updates every second Field of View 180 ˚ Spectral Range 250 to 400 nm Directional (Cosine Response) ± 10 % at 75 ˚ zenith angle Temperature Response Approximately 0.1 % per C Operating Environment -40 to 70 C, 0 to 100 % relative humidity Dimesions 24 mm diameter, 28 mm height Mass Sensor head weighs 90 g USB Cable 4.5 m (15 ft) Current Draw (when Logging) 61 mA Warranty 4 years against defects in materials and workmanship Manufactured Assembled in the USA