Italian to English Medical Medical: Pharmaceuticals

The text originally speaks of a testing on a" FS 4 ml" which I then understood as meaning fiala-siringa. I was tempted to translate this as a pre-filled syringe, but there is plenty of uses of "siringa pre-riempita" and should mean something else. It is a combination of vial and syringe or am I mssing something.

Example "FIALA-SIRINGA DA 4 ML STERILE USO INTRARTICOLARE A BASE DI SODIO IALURONATO 1,5% "