The battery lasts more than 300 hours. Maximum test range + 26dBm. High stability design, no power meter zero operation, improve the test efficiency. Up to ten calibration wavelengths: 830 nm, 850 nm, 980 nm, 1300 nm, 1310 nm, 1450 nm, 1490 nm, 1550 nm, 1590nm, 1625nm. Automatic wavelength recognition function. Automatic loss test function. Year accuracy assurance and recommended measurement cycle.