Abstract: A connector for use in an ultra-high vacuum system that has a metal conduit section with a first hardness, a metal fitting member with a second hardness greater than the first hardness of the conduit section, and a metallic reaction-inhibiting barrier positioned between the conduit section and the fitting member to sealingly attach the conduit section and fitting member together. The metal conduit section has a first end, a second end, and a flow path between the first and second ends. The metal fitting member has a rear face proximate to the second end of the conduit section, a front face facing away from the rear face, and an opening between the front and rear faces aligned with the flow path of the conduit section. The reaction-inhibiting member also has an aperture aligned with the flow path of the conduit section and the opening of the fitting member.