Features: Light weight and mini size for easy carrying. ABS material, comfortable feeling. Highly sensitive detector, fine stability, accurate measurement. Self calibration by user himself. Large rechargeable lithium battery supports continuous work for up long hours. LED lighting function, convenient for dark environment operation. LCD color screen, ultra-low energy consumption, clear display does not hurt the eyes. Automatically save the last tested wavelength when shutting down. 40 sets of data are automatically covered and stored in cycles. USB charging: universal interface, plug and use. Automatically save the last tested wavelength when shutting down. 40 sets of data are automatically covered and stored in cycles. USB charging: universal interface, plug and use. Power meter interface: 2.5mm SC/FC/ST