The combination of a syringe and needle cover that not only provides protection for the needle prior to use of the syringe but also facilitates the mating the syringe to a vial without exposing the needle to the user until the syringe is filled and ready for injection. Advantages include greater economy,...http://www.google.es/patents/US5520659?utm_source=gb-gplus-sharePatente US5520659 - Syringe needle cover and vial connector
