LDS Vacuum 133-VPA Kodial Glass Viewport

The LDS Vacuum 133-VPA is a premium zero-length viewport designed for UHV and high-vacuum applications where space is at a premium and optical access is required. With its 1.33″ OD CF (DN16CF) flange, welded construction, borosilicate 7056 (Kodial) glass window and included annealed copper gasket, it delivers reliable vacuum performance for research labs, instrument builders, universities and industrial R&D facilities. The compact design features six thru-holes (0.172″ bolt diameter), a 0.63″ clear view opening and a total flange thickness of just 0.5″—minimizing intrusion into the vacuum chamber. Suitable for repeated bakeouts (250–350 °F typical) when ramped carefully, this viewport must be installed with proper washers and torque, and is not rated for positive pressure service—exclusively for vacuum. Choose the 133-VPA when your system demands optical access, ultra-high vacuum integrity and minimal profile.