A used, but in good functional condition. Lab-Volt Computer Interface Base Unit with Built-In Power Supply. The item is designed to be utilized with Lab-Volt Modules. The computerized base unit can be is linked to the modules and can be linked to a computer automatically by the courseware. The coarse ware has to be purchase separately when needed, and can also be activated via a USB port by the teacher through a password-protected software. Circuit modifications (CM) and faults are switched in and out automatically by the software. A message on the student’s computer screen indicates that a CM or fault is activated. In the troubleshooting exercises, faults are also inserted automatically by the computer, thereby freeing the instructor to assist students with individual activities.