AGP Light Guide feedthroughs provide a simple and convenient means of introducing high intensity illumination into high and ultrahigh vacuum systems. Feedthroughs are offered in 1, 2, 3, or 4 light-path configurations on Conflat compatible CF, and ISO-NW KF flanges. AGP Light Guide feedthroughs are designed for use with standard flexible PVC and Stainless Steel bundled-fiber cables fitted with 3/16-Inch diameter (1/2-Inch long) barrel connectors. Each feedthrough path includes a hermetically sealed optical-grade sapphire substrate window for maximum vacuum integrity and optimal light transmission. Air and vacuum-side feedthrough interfaces include set-screws to securely lock cable connectors in place. Light sources and light guide cables are not offered by AGP, but can be procured from various optical suppliers, including Tri-Tronics, and others.