17/3/2009 · In order to avoid these risks, La-Pha-Pack has developped the so-called pre-cut septa. Here the Silicone carrier material is cut through in Y-form, however, the PTFElamination remains unhurt. As the Silicone part of the septa represents 95 per cent of the complete septa thickness, the needle can easily penetrate through the Y-slit for most of the septa’s thickness.