Patent ID: 8740854

Claim:
A plunger rod adapted for attachment with a stopper for use with a syringe barrel, said plunger rod comprising: (a) an elongated member having a front end and a back end and extending along a longitudinal axis; and (b) at least one deflecting arm having a first end secured to said front end of said elongated member, said deflecting arm having a second end extending in an outward direction and a rearward direction toward said back end of said elongated member, said deflecting arm being configured for deflecting radially inward during insertion of said plunger rod into the stopper and deflecting outward into an undercut space defined by an inner portion of the stopper and an undercut portion of the stopper and into contact with the inner surface of the stopper after insertion into the stopper to lock said plunger rod within the stopper, wherein the at least one deflecting arm cooperates with the undercut portion of the stopper to prevent separation of the stopper from the plunger rod.