Patent ID: 7665193

Claim:
A metallic double-sided element including a coupling head, a body portion disposed on the rear end side of the coupling head and a pair of right and left leg portions extending to the rear end side of the body portion, wherein the coupling head includes: thin flat plate portions whose thickness between its front surface and rear surface is smaller than that of the body portion; coupling convex portions projecting in the front surface-rear surface direction at a central portion in the right-left direction of the thin flat plate portion; right and left raised portions which are raised in the front surface-rear surface direction from the thin flat plate portions disposed on the right and left sides of each of the coupling convex portions, and extend to the body portion so as to be integrated with the body portion; and a coupling concave portion which is formed to be continuously surrounded by a peripheral wall of one of the coupling convex portions, the right and left raised portions and the body portion, wherein each of the right and left raised portions has a slope portion which is inclined from a front edge on the coupling convex portion side of the raised portion toward the body portion such that the slope portion rises with respect to the front surface and rear surface of the thin flat plate portion, the right and left raised portions being formed between both right and left side edges of he element with the one coupling convex portion and the coupling concave portion interposed therebetween, and part of each inside face of the right and left slope portions is integrated with part of right and left side faces of the coupling convex portion in a face bonding manner.