[High Efficiency] Easy identification of fiber breakpoints, poor connections, bending, or cracking for finding the correct fiber to splice or quickly locating faults. A 30mW Visual Fault Locator emits a 650nm bright red light for fiber tracing, fiber routing, and continuity checking. Breaks or faults in the fiber refract the light, creating a visible glow around the faulty area. [Functions] This fiber optic tester is ideal for field testing, featuring constant output power, multi-interface compatibility, low battery warning, extended battery life, and long-distance detection. It delivers high brightness and operates on standard AA batteries. [Widely Used] 2.5mm universal connector compatible with ST, FC, SC, LC, and other common fiber optic connectors, accommodating both round and square-shaped interfaces. [Long Output Distance] The 30mW visual fault locator provides strong output power, projecting a clear red indicating light effective up to 20–30 km. Its high-efficiency power supply circuit ensures stable operation. [Crash-Proof and Dust-Proof Design] Features a stainless steel pen head and aluminum body for impact and dust resistance. ESD-safe case grounding prevents electrostatic discharge damage. Batteries: Two 1.5V AA batteries (not included) Color: Green + Black Material: Aluminum alloy Package Contents: 1 x Fiber Identifier Note: Screen and lighting conditions may cause slight color variation between the image and the actual product. Measurement tolerance: ±1–3 cm.