The improved vial transfer assembly or vial transferset may be attached to a vial under sterile conditions and used to transfer fluid to or from a conventional vial. The transferset includes a tubular transfer member which is sealingly supported on the rim portion of a vial stopper, a piercing member...http://www.google.es/patents/US6003566?utm_source=gb-gplus-sharePatente US6003566 - Vial transferset and method
