Sealing and replenishment gasket

An annular sealing and replenishment cup with axis Δ, which is intended to be positioned between a hydraulic cylinder (3) and piston (4) and which has a <<U>> axial section comprising:

• a static branch (10) defining a static sealing annular lip (11),
• a dynamic branch (12) defining a dynamic sealing annular lip (13),
• and a core (14) connecting the static (10) and dynamic (12) branches and defining an annular bead (15) opposite the lips,
• wherein the core (14) includes a rotation area and a stiffness area, rotation area defined by a first connecting surface (24) adjacent the static branch (10), located opposite the bead (15), and having a concave shape corresponding to a local reduction in the thicknesses of the static branch (10) and of the core (14) at the connecting region between the static branch (10) and the core (14), the stiffness area having a core thickness greater than the rotation area and a second connecting surface between the first connecting surface (24) and the dynamic branch (12), the rotation area (21) allowing the dynamic branch (12) and the core (14) as a whole to be displaced relative to the static branch.