SEEGER Runddrahtsprengringe f Wellen DIN 7993A-FeSt RW 8

When oil is used alone as a rust inhibitor, the oil provides a hard but flexible finish that expels any excess moisture and air. It displaces moisture and air from rusted metal and thus puts rust in its place.

Spring steel is a steel that has a higher strength compared to other steels, but with very high elasticity. Tension discs and disc springs are made of spring steel so that the spring forces defined in the standard can be achieved.

The term plain indicates a completely untreated, merely oiled, smooth surface for all DIN and ISO screws such as wood screws, hexagon head screws, threaded rods, nuts and many types of washers.