Abstract: Disclosed is a plunger piston for use in a syringe and especially in a micro-dosing syringe pump application. The plunger piston comprises a front face opposite a rear face and at least one annular groove positioned between the front face and the rear face. The plunger piston includes a plurality of channels extending from the front face into the groove, the channels providing communication between the front face and the groove. An O-ring is received in the groove and the channels serve to equalize pressures around a first side of the O-ring to improve sealing performance and micro-dosing accuracy of a syringe or a micro-dosing syringe pump utilizing the plunger piston.

Abstract: Medication delivery system including a container, reservoir, or chamber for medium or fluid, and a mechanism or driving components configurable outside of medium or fluid chamber for advancing a plunger to dispense medium or fluid. The system can include syringe-style drug container, reservoir, or chamber, containing medium or fluid dispensable by advancing plunger disposed inside the container, where the container includes a sliceable portion and where a cutter or slicer is configurable on plunger holder or pusher behind plunger such that cutter cuts through sliceable portion of container as plunger is advanced dispensing medium out of container. The present disclosure is further directed to a patch pump comprising the system as described above. The present disclosure is further directed to a medicament delivery device comprising the system as described above.

Abstract: Provided is a fill closure tab or an infusion device incorporating the same. The fill closure tab includes a gripping portion, and seals an insertion mechanism opening with a hydrophobic membrane. The fill closure tab further includes a fill assist mechanism shaped to assist with directing a filling device such as a pen needle or syringe to a fill port of the infusion device.