Check the listing for details. Jennings JCS-400 Fixed Glass Vacuum Capacitor. Condition: Used, Made in United States. Listed at 120.00 USD. From the private estate of a professor of electrical engineering and ham radio operator. Untested, but visual inspection reveals no cracks or loose connections. No reason he would keep bad components. The Jennings JCS-400 Fixed Glass Vacuum Capacitor is a vintage electronic component manufactured by Jennings in the United States. This capacitor is designed with a glass envelope to eliminate leakage and provide a stable capacitance value over time. The JCS-400 model is known for its quality and reliability, making it a sought-after product for vintage audio and video equipment restoration projects. Its sturdy construction and consistent performance make it a valuable addition to any collector's inventory of vintage electronics.