Huanyu Huanyu Instrument mainly provides instruments and tools. Features : Auto-sensing probe: Automatic, fast, effective, and true measurement results using microprocessor technology Snap-on battery back cover: Demolition is more convenient, using 9V battery, longer battery life. However, due to international transportation, batteries are NOT included. Pls kindly understand. Specifications: Product Name: High Precision Solar Power Meter Product Model:SM206 Display: 3-3/4 LCD display Resolution: 0.1W/m2, 0.1Btu/(ft2h) Accuracy: ±5%, ±10W/m2 of measurement Temperature coefficient: ±0.38W/m2/°C Drift: <±3%/year Overload display: OL Sample time: 0.25 seconds/time Test range: 0.1-3999W/m2, 1-3999W/m2 Note: Align the probe directly with the light sourcethe probe can be directly aligned with the light source to automatically measure when used. Please keep the probe clean and avoid affecting the measurement results.