The Model 50-9 has 7 dual color LEDs that monitor leads 2, 3, 4, 5, 6, 8 and 20, plus over 50 sockets for jumpering RS-232 signals. Data bias can be inferred from the color of the LEDs, and signal level can be inferred from color intensity. An all-black case and brighter LEDs provide greater color clarity and contrast. In addition, the Model 50-9 has pin jack sockets which allow RS-232 leads to be wired or jumpered in any configuration. Three sets of sockets allow multiple leads to be easily jumpered together. For added convenience, the two sections may be taken apart and used independently.