Abstract: The invention relates to a magnetic holding device (10), in particular a clamping device, comprising a holding surface (9) and at least one first permanent magnet (11), characterized in that the holding device (10) comprises at least one second permanent magnet (12) which is rotatably mounted relative to the at least one first permanent magnet (11) about a rotational axis (3), whereby the pole direction (2) of the second permanent magnet (12) is rotatable relative to the pole direction (1) of the first permanent magnet (11).

Abstract: The invention relates to a component part produced from a polymer/boron nitride compound, wherein the polymer/boron nitride compound comprises at least one polymer material, at least one thermally conductive filler, and at least one reinforcing filler, and wherein the at least one thermally conductive filler comprises boron nitride agglomerates. The invention further relates to a polymer/boron nitride compound for producing such a component part. The invention further relates to the use of such a component part for thermal conduction to control the temperature of component parts or assemblies, preferably electronic component parts or assemblies.