With a powerful 10mW output, the Light Pen emits a bright, visible red laser beam that can easily trace the path of fiber optic cables and detect any faults or breaks along the cable. This essential tool is ideal for technicians and engineers involved in the installation, maintenance, and troubleshooting of fiber optic systems. As a visual fault identifier (VFI), it can quickly identify faults in fiber optic jumper cables, distribution frames, patch panels, and splice trays. For single mode, multimode and plastic fibers, this is a low price fiber laser light tester that complies with the latest. It looks like a flashlight or a pen-like instrument with a light bulb or LED source that mates to a fibre optic connector.