The TL-2-A Tally Light from Digital Arts is compatible with devices featuring an 3.5mm TRS 5V tally output port such as the TriCaster 300 and various BirdDog NDI converter boxes. You can also use it in your DIY tally system. The TL-2-A provides the talent and camera operator with a bright tally light and LED status indicators. It's camera mountable and features internal current limiting resistors.