Abstract: A thermoplastic housing has a chamber open at one end and a bottom wall at the other end. A thermoplastic rotor is locked axially in the chamber by a snap fitting ridge and groove. A one or more bores are in the housing bottom wall in communication with the chamber. The rotor has a central boss with one or more bores aligned with the housing bores in an initial position of the rotor and includes an outer ring with axially depending radially flexible pawls which engage housing ratchet teeth in the chamber. The pawls and teeth rotationally lock the rotor relative to the housing in one direction while seal filament segments inserted in the aligned bores are twisted about each other or about a post in the cavity. The rotor is rotated relative to the housing manually by finger gripped-flanges attached to the rotor and to the housing. The rotor ring and boss are spaced by a weakening groove which causes the boss to permanently separate from the ring when the filament is pulled in an attempt to defeat the seal.