The Praxair ProStar 41V35 Medium Black Cap is a TIG welding torch back cap designed for use with Airco(R) and LINDE(R) style TIG torches. Manufactured by Lincoln Electric in China, this back cap is compatible with Series 9 or 20 Series TIG torches. With a medium size and a pack of 3, it is a high-quality accessory for welding and soldering equipment in various industrial applications.