Abstract: A tube connector for sealing a flareless tube to a fitting having a flat sealing face perpendicular to the fitting axis. The tube connector incorporates a ferrule engaged by a sleeve mounted on the end of the tube and having a flat radial surface for engaging the fitting sealing face. The ferrule is deformable and establishes a primary wedge type metal-to-metal sealing engagement with the tube by a compression nut threaded upon the fitting. The ferrule radially bows under axial and radial compression and this deformation suppresses vibration while the shape of the ferrule end engaged by the nut increases the radial forces on the ferrule as the nut is tightened to provide firm tube support remote from the seal region. The sleeve is provided with an internal undercut adapted to outwardly flare the end of the tube to lock the tube to the sleeve, and radially support the tube end as the tube is compressed during connection.