J-Deal TL510C Hand-held Optical Power Meter + 1mW Visual Fault Locator Fiber Optic Cable Tester Meter for CATV CCTV Telecommunications Engineering Maintenance Cabling System Type C: Measurement range: -50~+26dBm; High measurement accutracy and display resolution Common interface design: FC/SC/ST interface, with standard FC, SC adapter interface Auto-off function; Backlight LCD display; AAA batteries which is more convenient to carry; Small size, easy to field test. High quality pen type visual fault locator Functions: Finding the breakpoints, poor connections, bending or cracking in fiber optic cables