Septa

A system for sealing a vessel, the

• system comprising:
• a cap comprising an opening;
• and
• a septum configured to engage with the cap, the septum comprising:
• a wholly hollow upper portion having a first width, wherein the upper portion is resiliently deformable having a tapered wall portion to be passed through the opening of the cap from an inner side of the cap to an outer side of the cap;
• a second portion located between the upper portion and a lower portion, the second portion having a second width smaller than the first width, the second portion being sized and shaped to be received by the opening and compress against portions of the cap that define the opening;
• the lower portion having a third width larger than the second width and a lower horizontally planar surface across the entire width of the third portion constructed and arranged to form a seal with a lip of the vessel when the septum is attached to the vessel with the cap;
• and
• an inert coating disposed on the lower horizontally planar surface of the lower portion, wherein the septum is configured for puncture for fluid movement through the septum and to the vessel, from the vessel, or combination thereof, wherein the inert coating comprises polytetrafluoroethylene and the upper portion or the second portion comprises an elastomeric material.