Fault detection plays an important role in fiber optic network installation and maintenance. This handheld visual fault locator simplifies the process by using a 650nm semiconductor laser to inject visible red light into optical fibers, allowing users to quickly identify breaks, bends, or poor connections by observing light leakage points. It is suitable for bare fibers, patch cords, and other fibers where red light can escape. When used alongside an OTDR, it compensates for near-end blind zones, improving troubleshooting. Additionally, it serves as a practical tool for identifying individual fibers in multi-core cables or ribbon fiber assemblies.