PFAS-Free Syringe Plunger Stopper With Curved Inter-Rib Region

A stopper free or substantially free of per- and poly-fluoroalkyl substances (PFAS) and adapted for attachment with a plunger rod for use within a syringe barrel, the stopper comprising:

• a main body portion defining a proximal end and a distal end, the proximal end configured to mate with a distal end of the plunger rod, to secure the stopper to the plunger rod;
• a plurality of ribs each extending from an outer surface of the main body portion and around an outer circumference of the main body portion, the plurality of ribs including at least a first rib and a second rib spaced from the first rib and
• an inter-rib region positioned between each pair of adjacent ribs of the plurality of ribs, characterized in that the inter-rib region comprises a curved inter-rib region where the outer surface of the main body portion is curved radially inward.