| 摘要 |
A nail-shaped fastening element having a stem, and a head (3, 13, 23, 33) provided at one end of the stem and projecting radially beyond the stem with the stem tapering at its another, free end toward a tip (5, 15, 25, 35) and having a spherical, first section (1, 11, 21, 31) extending from the tip (5, 15, 25, 35) in a direction toward the head (3, 13, 23, 33), and a second conical section (2, 12, 22, 32) adjoining the first section (1, 11, 21, 31) and having a length (L2, L12, L22, L32) smaller than a length (L1, L11, L21, L31) of the first section (1, 11, 21, 31). |
