High efficiency: Easy identification of fiber breakpoints, poor connections, bending, or cracking for finding the right fiber to splice or quickly locating faults. The 30mW visual fault locator emits a 650nm bright red light for fiber tracing, fiber routing, and continuity checking. Breaks or faults in the fiber will refract the light, creating a visible glow around the faulty area. Functions: The fiber optic tester is ideal for field testing with features including constant output power, multi-interface compatibility, low battery warning, extended battery life, and long-distance detection. Super bright output powered by convenient AA batteries. Widely used: 2.5mm universal connector designed to fit ST, SC, LC, and other fiber optic interfaces, both round and square types. Long output distance: The 30mW visual fault locator delivers strong output power, emitting a bright red light detectable up to 20-30 kilometers. High-efficiency power circuit ensures stable performance. Crash-proof and dust-proof pen-style design: Features a stainless steel tip and aluminum body for durability. Grounded case design helps prevent ESD damage. Battery: Two 1.5V AA batteries (not included) Color: Green + black Material: Aluminum alloy Package Contents: 1 x fiber optic visual fault locator Note: Light and display differences may cause slight color variation between the image and actual item. Measurement error allowed within +/- 1-3cm.