[High efficiency] Easily identify fiber breakpoints, poor connections, bending or cracking. Ideal for locating the correct fiber to splice or quickly detecting a fault. Our 30mW Visual Fault Locator emits a 650nm bright red light for efficient fiber tracing, routing, and continuity checking. Breaks or faults in the fiber will refract the light, producing a bright glow around the defective area. [Excellent Functions] This fiber optic tester is perfect for field tests due to its multiple functions, such as constant output power, multi-interface adaptability, low battery warning, long battery life, and long-distance detection. It features a super bright output and is powered by convenient AA batteries. [Widely Used] 2.5mm Universal Connector - the detector's connector is designed to be compatible with various types of fiber optic cables, including ST, SC, and LC connectors in both circular and square shapes. [Long Output Distance] The 30mW visual fault locator possesses a powerful light source output, capable of projecting a strong red indicating light over distances of up to 20-30 kilometers. The high-efficiency power supply circuit ensures a stable power delivery. [Crash-proof and Dust-proof Design for Pen Head] Constructed with a stainless steel head and aluminum body to prevent damage and dust accumulation, along with a ground design that effectively guards against ESD damage. Batteries: Two 1.5V batteries (not included) Type: A Colour: Green + Black Material: Aluminum alloy Package Contents: 1 set x fiber identifier Only the above package content; other products are not included. Note: Lighting and different displays may cause the color of the item in the picture to differ slightly from the actual product. The allowed measurement error is +/- 1-3cm.