Aspirating piston and plunger coupling

Claim 1

A HOLDER COMPRISING A BARREL ADAPTED TO RECEIVE A CARTRIDGE WITH A PISTON THEREIN, SAID PISTON HAVING A COUPLING BUTTON HAVING A HEAD WITH AN UNDERFACE OF THE HEAD PERPENDICULAR TO THE LENGTH OF THE PISTON, A HUB, FORMING PART OF THE HOLDER, PROVIDED WITH A BORE THERETHROUGH, A PLUNGER SNUGLY SLIDABLY RECIPROCATIVE IN SAID BORE, SAID PLUNGER COMPRISING A FURCATED PORTION FORMING A PLUNGER PORTION SLIDABLE IN THE BORE, AND SAID FURCATED PORTION TERMINATING IN FINGERS DIRECTED TOWARD EACH OTHER ADAPTED TO ENGAGE BENEATH THE HEAD OF THE BUTTON ON THE PISTON, WHEN THE FINGERS ARE BROUGHT TOGETHER, THE FACE OF THE FINGERS ADAPTED TO DIRECTLY ENGAGE THE UNDERFACE OF THE HEAD BEING BEVELLED TO PERMIT EASY DISENGAGEMENT OF THE PLUNGER FROM THE PISTON IN A PREDETERMINED REGION OF THE PLUNGER WITH RESPECT TO THE BARREL.