A plurality of connecting elements projects from a surface of an article. Each connecting element includes a first stalk and second hollow stalk projecting from the surface. The second stalk is generally coaxial with the first stalk and spaced apart from the first stalk defining a radial gap therebetween....http://www.google.co.uk/patents/US7997921?utm_source=gb-gplus-sharePatent US7997921 - Connecting elements having a stub surrounded by a hollow stalk with a flange
