Sealing cap and method for manufacturing a sealing cap

Sealing cap (1) with body (3) with a U-shaped cross-section with a base (9) and a perimeter wall (7) of height H characterised in that it is made of an elastically-deformable substrate (4) made of a material with a first Young's modulus, the perimeter wall comprising an open end provided with means (823-823′″) to reduce a rigidity of the open end;

• wherein the elastically-deformable substrate is coated at least on an exterior of the perimeter wall with a layer of a resilient material (5) with a second Young's modulus, wherein the second Young's modulus is lower than the first Young's modulus, the base (9) is provided with a continuous convex ridge (12) adjacent the perimeter wall, the continuous convex ridge surrounds at least one concave trough (16) and characterised in that said at least one concave trough surrounds a further convex ridge (13), wherein the perimeter wall is configured without a contiguous aperture positioned in the perimeter wall away from an edge of the perimeter wall.