Abstract: A plurality of connecting elements projects from a body's surface. A plurality of indents is defined in the body's surface. Each stem element includes first and second stalks projecting orthogonally from the surface. The first stub includes a pyramidical cap section and at least one generally planar wall. The second stalk is generally parallel to the first stub and spaced apart from the at least one wall, defining a gap therebetween. The second stalk includes a stem projecting from the surface. A lip section extends from a distal end of the stem and protrudes outwardly relative to the stem. An engagement section extends from the lip section. A free end of the engagement section defines a distal end of the second stalk. An outer surface of the engagement section defines a first gradient tapering from the lip section to the distal end of the second stalk.

Abstract: A plurality of connecting elements projects from a body's surface. A plurality of indents is defined in the body's surface. Each stem element includes first and second stalks projecting orthogonally from the surface. The first stub includes a pyramidical cap section and at least one generally planar wall. The second stalk is generally parallel to the first stub and spaced apart from the at least one wall, defining a gap therebetween. The second stalk includes a stem projecting from the surface. A lip section extends from a distal end of the stem and protrudes outwardly relative to the stem. An engagement section extends from the lip section. A free end of the engagement section defines a distal end of the second stalk. An outer surface of the engagement section defines a first gradient tapering from the lip section to the distal end of the second stalk.

Abstract: 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. The first stalk includes a cap section. The second stalk includes a stem projecting generally orthogonally, at a proximal end thereof, from the surface. A flange section having a first wall thickness extends from a distal end of the stem and has an outer diameter greater than an outer diameter of the stem at the distal end. An engagement section extends from the flange section. A free end of the engagement section having a second wall thickness defines a distal end of the second stalk and has an outer diameter less than the outer diameter of the flange section.

Abstract: An article includes a plurality of stems projecting from a surface thereof. Each stem includes a hollow stalk projecting orthogonally from the surface and a hollow head defined on a distal end of the hollow stalk. The head includes a flange section extending from the distal end of the hollow stalk and having an outer diameter greater than an outer diameter of the hollow stalk at the distal end. A cap section extends from the flange section, defines a distal end of the stem and has a generally convex contour. The cap section has a first wall thickness at the distal end of the stem, a second wall thickness at a junction of the cap section and the flange section and a third wall thickness at a circumferential section intermediate the distal end and the flange section. The third wall thickness is less than the first and second wall thicknesses.