HECO-TOPIX-plus Kombisechskantkopf T-40 8,0 x 140, znb

Steel is an iron-carbon alloy with a maximum carbon content of 2% by mass. The steels achieve their intended physical and mechanical properties through various hardening, annealing and tempering processes. It is also possible to harden the edge zone by surface hardening, case hardening or nitriding. Well-known steel grades are structural steels, free-machining steels, case-hardening steels, nitriding steels, tempering steels, tool steels and stainless steels.

Electroplating is a so-called electrolytic process. The coating is applied in accordance with the DIN EN ISO 4042 standard. Blue-passivated surfaces appear white to blue or with a bluish iridescence. Coating thickness: 8–10 my.

The wrench sizes for hexagonal bolts and nuts are specified in ISO 272: 1982-01. The additional internal hexagon/T-drive is used for re-tightening or in confined spaces. Torque is transmitted more directly via the radial sections of the tooth flanks rather than via the almost tangential surfaces of the hexagon.