Patent ID: 7909057

Claim:
A valve insert, comprising: a ring, made of a resilient material, having shape is defined by the rotation of an irregular polygon around a central axis, said irregular polygon is formed by superposing a quadrilateral and a circle wherein: said quadrilateral is a plane figure including: a first side being connected to a second side at a first interior angle; a third side being connected to said second side at a second interior angle; a fourth side being connected to said third side at a third interior angle; said fourth side being connected to said first side at a fourth interior angle; said first side being longer than said fourth side; said fourth side being longer than said second side; said second side being longer than said third side; said first interior angle and said second interior angle both being right angles; said third interior angle being an obtuse angle; and, said fourth interior angle being an acute angle; said circle is a plane figure including a center and a radius, and said radius being shorter than said third side of said quadrilateral; said center of said circle being positioned within said quadrilateral; said circle crossing said first side and said second side.