of the base 12 in one embodiment the puncturing shaft 20 can be substantially perpendicular to the first side 14 of the base 12 the puncturing shaft 20 can be substantially centrally located on the first side 14 of the base 12 the puncturing shaft 20 can include a stem portion 22 that can extend directly from the first side 14 of the base 12 the stem portion 22 can transition to a cannula portion 24 the cannula portion 24 can culminate in a tip 25 which may be pointed or chamfered to facilitate puncturing the transition between the stem portion 22 and the cannula portion 24 can have any suitable configuration for instance the transition between the stem portion 22 and the cannula portion 24 can include a shoulder 26 which may determine an insertion length of the puncturing shaft 20 into the container in one embodiment the stem portion 22 and cannula portion can each have a substantially circular cross section with the diameter of the circular cross section of stem portion 22 being greater than the substantially circular cross section diameter of the cannula portion 24 thereby forming the shoulder 26 the cannula portion 24 can include a plurality of serrations teeth or barbs not shown for resisting any tendency of the cannula portion 24 from accidentally withdrawing from the item into which it is inserted such as the.