A needle assembly and cylindrical cover housing which are usable with a conventional hypodermic syringe. The needle assembly has a circular mount on it with catch slots and slanted surfaces. The cover housing has inward projections which are flexible so that the hypodermic syringe can be received in...http://www.google.de/patents/US4927018?utm_source=gb-gplus-sharePatent US4927018 - Disposable covered needle safety assembly
