The product is a vintage Sprague Vitamin Q glass sealed capacitor with a capacitance of .1 microfarads and a tolerance of ±20%. It operates at a maximum voltage of 3000 volts DC. These capacitors were commonly used in vintage audio and electronics applications for their quality and reliability. The Sprague Vitamin Q brand is known for producing high-performance capacitors for a variety of applications, making this a desirable choice for vintage electronics enthusiasts and collectors.