Abstract: A vial and syringe connector assembly is provided for the sterile addition of fluid material to a sealed container having an injection-type access port. The assembly comprises a syringe connector which carries a hollow, injection needle having one pointed end for passing through such access port. The other needle end is blunt. An open mouthed vial for the fluid material has an elastomeric sealing piston disposed in the vial mouth and movable in sealing relation axially of the vial. A bore is also defined axially in the sealing piston of a size to receive the blunt end of the needle. An elastomeric diaphragm which is integral with the sealing piston occludes the bore. The vial and sealing piston are carried on the syringe connector with the blunt needle end positioned in the bore. The blunt needle end is used to rupture the diaphragm for fluid flow through the needle of the contents of the vial without accidental "coring" of the diaphragm and consequent obstruction of flow through the needle.