Features ★ Large measurement range & 6 calibration wavelengths - Optical Power Meter fiber optic tester can provide an optical power measurement range of -70 - 80 dB, an absolute optical power measurement and a relative power measurement. Calibration wavelengths: 850nm, 1300nm, 1310nm, 1490nm, 1550nm and 1625nm. ★ Fast response and measurement - When the output power changes, Fiber Optical Power Meter it can display quick tracking and real-time measurement of optical power. ★ Precise measurement - high measurement accuracy and resolution of backlit LCD display with user self-calibration function. The fiber optic tester requires 3 x AAA batteries (not included), has a long battery life. ★ Battery Operated - The fiber optic tester requires 3 x AAA batteries (not included), easy to use real-time monitoring and battery level display. When the battery level is low, a warning message is displayed and an automatic shutdown function is activated. ★ Customer Service - We are committed to meeting our customers' needs to produce the best products. If you have any suggestions or requests, you can contact us at any time so that we can do our best to answer you as quickly as possible. Specification: Item Type: Optical Tester Material: Plastic Product Model: TL510 Measuring range dBm: -70~+10dBm (the best actual measuring range is -65~0dBm) Wavelength Range (nm): 800-1650 Calibration wavelength: 850nm, 1300nm, 1310nm, 1490nm, 1550nm, 1625nm Detector: InGaAs Accuracy: <±3% (-10dBm. 22°C) Resolution: Linearity: 0.1%, Non-linearity: 0.01dBm Working temperature: -10℃-+50℃ Storage temperature: -20℃~+70℃ Relative Humidity: 90% (+ 30°C) Connector: Detachable for FC/PC SC/PC Power: 3 AAA batteries (delivered without batteries) Working time: > 120 hours (no backlight) Package List: 1 x Optical Power Meter (Battery not included) 1 x Adapter Head 1 x Storage Bag 1 x Instruction Manual Package List 1 x Optical Power Meter(Battery Not Included) 1 x Adapter Head 1 x Storage Bag 1 x Manual