Patent ID: 8740856

Claim:
A stopper adapted for attachment with a plunger rod for use within a syringe barrel, said stopper comprising: (a) a main body defining an open rearward end and a closed front end, said open rearward end adapted to receive a front forward end attachment portion of such plunger rod, said main body including an inner surface; (b) a core member integrally formed with said main body adjacent said closed front end, said core member including a nose portion having a conical tip configured for entering an outlet opening of the syringe barrel, said core member including a stopper center post protruding from an interior of the core member toward the open rearward end, said stopper center post including a back core portion adapted for contact with said front forward end attachment portion of the plunger rod; (c) at least a first rib extending radially outward around a perimeter of said main body; and (d) a taper provided on said inner surface of said main body, said taper adapted for contact with a corresponding taper on the front forward end attachment portion of the plunger rod, said taper and corresponding taper cooperating together to cause the stopper to apply a radial force to the syringe barrel upon the application of a forward force to the plunger rod.