User Select 3 Ranges: 0.00 – 1999 Lux 2000 – 19999 Lux or 20000 TO 50000 Lux – Range Settings Through Key Buttons, Resolution 1 Lux / 10 Lux / 100 Lux; Accuracy +/- 6% -- Peak Wave 560nm with Silicon Photodiode Waterproof Sensor, 9 volt Battery