Features MAIN FUNCTION --- Handheld optical power meter series products are mainly used for measuring the power of continuous optical signals. Adopting a single chip microprocessor for control, with complete functions. WIDELY APPLICABLE --- Widely used in fields such as fiber optic construction and maintenance, fiber optic communication, fiber optic sensing, and optical CAT. EASY TO USE --- Optical power meter adopts a built in detector, which can provide good protection. Compact appearance, automatic shutdown function, wavelength memory function, manual calibration, fiber optic work recognition, and wide testing range. MULTIFUNCTIONAL --- Supports lighting, automatic shutdown, memory wavelength function, working frequency recognition, and user calibration. SUPPORTS SC, FC, ST INTERFACES --- Supports external power supply such as power banks and computers, supports linear (nW) and nonlinear indicators (dB), and supports extended battery life. Specification: Item Type: Optical Fiber Power Meter Material: ABS Wavelength Range: 800 to 1700 Probe Type: For InGaAs Measurement Range: -70 to +10 Uncertainty: ± 5% Standard Wavelength (nm): 850, 980, 1270, 1300, 1310, 1490, 1550, 1577, 1625 Display Resolution: Linear Display: 0.1% Logarithmic Display: 0.01dBm Frequency Identification (Hz): 270, 1000, 2000 Static Current: Less than or equal to 18uA Working Current: Less than or equal to 25mA Range Time: Greater than or equal to 20H Charging Voltage: 5V Charging Current: Less than or equal to 500mA Charging Duration: Less than or equal to 3H Automatic Shutdown Time (min): 10 Power Supply: Rechargeable lithium battery, external input Battery: Rechargeable lithium battery 400mAh x 1 [shipped with built in battery] Package List:1 x Fiber Optic Power Meter  1 x USB Cable  1 x Portable Rope  1 x Manual  Package List 1 x Fiber Optic Power Meter 1 x USB Cable 1 x Portable Rope 1 x Manual