Red light source - Visual Fault Locator (VFL) for checking the correct polarity of the fiber optic link and verifying for interruptions. It allows for fault checking of single-mode and multi-mode fibers as well as other fiber optic components (e.g., fiber or connector breaks). The CableMaster VFL is used for continuity testing and fault locating in optical fibers and components in both single-mode and multi-mode applications. Depending on the use, a range of over 5 km can be achieved. A universal adapter enables connection to all common optical 2.5 mm connector systems (e.g., SC). Additionally, a screwable adapter for 1.25 mm (e.g., LC) is available. The operating time in blink mode is approximately 40 hours. With its compact and ergonomic design, the visual fault detector is ideal for daily use in all fiber optic applications, such as in data centers, outdoor use, industrial environments, and laboratories. The CableMaster VFL from Softing IT Networks stands out for its practical features, including its special anti-roll shape, non-losing dust cap, and handy design. The CableMaster VFL is easy to operate with one hand and is powered by two standard AAA batteries. With the practical carrying loop, the fault detector can be hung up whenever needed.