The process used in joining Corning 7052 Borosilicate glass (or equivalent) to an expansion-matched Kovar (NiFeCo alloy) transition tube is a highly specialized technology. Accu-Glass offers a wide selection of durable and reliable high and ultrahigh vacuum glass-to-metal tubular adapters. Our glass-to-metal adapters are available in rigid and flexible (with stainless steel bellows) configurations and fitted with industry standard ISO or CF vacuum flange mounts. These adapters are designed for simple and reliable installation of 'tubular' laboratory glass instruments onto 'metallic' high and ultrahigh vacuum systems and/or the attachment of standard metal vacuum components onto glass laboratory apparatus. Single and double-ended flanged configurations with open, closed, rigid and flexible interfaces are available. Single-ended devices have either open or closed (domed) glass tube terminations on the end opposite the vacuum flange mount. UHV rated adapters are fitted with Conflat compatible, metal seal CF flanges, while HV rated devices use standard, elastomer seal, quick-release ISO flanges.