Tips: This product is only available in Chinese and can be equipped with an English manual NF-866 Telecom Check Telephone Line Check Survey Line Tester Alligator Clip Telephone Tester Product Description Features: 1. FSK and DTMF caller ID display, automatic detection. 2. Redial, callback, flashing function. 3. 16 Groups of outgoing call storage. 4 . 62 groups of dynamic call storage. 5. 32-bit pre-dialing and error correction function. 6. Backlight:Adjustable brightne. Technical index: NF-866 Technical Parameters Environment temperature -10-and40 Relative Humidity 10 percent - 95 percent Atmospheric preure 86-106kpa Environment Noise 70dB(A) Transfer indications Send loudne aeed value Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.