Air filter means

Claim 1

AIR FILTER MEANS FOR USE WITH A DUAL FLOW PIERCING DEVICE AS USED WITH INTRAVENOUS INJECTION APPARATUS, SAID FILTER MEANS COMPRISING AN ELONGATED HOLLOW BODY MEANS DEFINING A BORE EXTENDING LONGITUDINALLY THERETHROUGH, SAID BODY MEANS INCLUDING A FIRST OPEN END PORTION, SAID BODY MEANS INCLUDING AN INTERMEDIATE PERIPHERALLY EXTENDING INWARDLY DIRECTED WALL PORTION FORMED THEREWITHIN HAVING A HOLE FORMED THERETHROUGH, PLUG MEANS SECURED WITHIN THE OPPOSITE OPEN END PORTION OF SAID BODY MEANS, SAID PLUG MEANS HAVING AN END WALL PORTION DEFINING AN OPENING FOR THE ENTRANCE OF AIR THERETHROUGH, FIRST FILTER MEANS DISPOSED WITHIN SAID PLUG MEANS FOR FILTERING BACTERIA OUT OF AIR ENTERING THROUGH SAID LAST-MENTIONED OPENING, AND SECOND FILTER MEANS DISPOSED BETWEEN SAID PLUG MEANS AND SAID INTERMEDIATE WALL PORTION, SAID SECOND FILTER MEANS COMPRISING A DISC-LIKE MEMBER HAVING THE PERIPHERAL EDGES THEREOF CLAMPED BETWEEN ONE END OF SAID PLUG MEANS AND SAID INTERMEDIATE WALL PORTION, SAID SECOND FILTER MEANS BEING PERVIOUS TO AIR AND SUBSTANTIALLY IMPERVIOUS TO LIQUID.