A wireless communication device with a holder configured to be attached to a helmet strap, comprising: a speaker contained in a first flattened housing which defines a main internal face, associated with the speaker and intended to face a user ear, a main external face, and a perimeter connecting a perimeter area of the main internal face and of the main external face; a microphone, wherein the microphone is contained in a second housing connected to and distanced from the first housing by a rigid or deformable duct; a battery and an antenna are connected to the speaker and the microphone and are contained in said first and/or second housing (10, 20); characterised in that the holder includes a first anchorage, facing the main external face of the first housing and including several elastically deformable legs arranged around the perimeter of the first housing, said legs attaching the first anchorage to the perimeter of the first housing, the holder further includes a second anchorage, adjacent to and attached to the first anchorage, intended to be fixed to the helmet strap; and wherein the perimeter of the first housing is shaped as a regular polygon with at least six faces and the elastically deformable legs are configured to undergo deformation when the first housing with a polygonal perimeter rotates with respect to the first anchorage, but without releasing the first housing during said deformation; or the perimeter of the first housing is circular and the elastically deformable legs of the first anchorage are configured for exerting elastic pressure on said perimeter of the first housing, hindering the free rotation thereof; enabling the first housing to be positioned at different angular positions to the first anchorage. a speaker contained in a first flattened housing which defines a main internal face, associated with the speaker and intended to face a user ear, a main external face, and a perimeter connecting a perimeter area of the main internal face and of the main external face; a microphone, wherein the microphone is contained in a second housing connected to and distanced from the first housing by a rigid or deformable duct; a battery and an antenna are connected to the speaker and the microphone and are contained in said first and/or second housing (10, 20); characterised in that the holder includes a first anchorage, facing the main external face of the first housing and including several elastically deformable legs arranged around the perimeter of the first housing, said legs attaching the first anchorage to the perimeter of the first housing, the holder further includes a second anchorage, adjacent to and attached to the first anchorage, intended to be fixed to the helmet strap; and wherein the perimeter of the first housing is shaped as a regular polygon with at least six faces and the elastically deformable legs are configured to undergo deformation when the first housing with a polygonal perimeter rotates with respect to the first anchorage, but without releasing the first housing during said deformation; or the perimeter of the first housing is circular and the elastically deformable legs of the first anchorage are configured for exerting elastic pressure on said perimeter of the first housing, hindering the free rotation thereof; enabling the first housing to be positioned at different angular positions to the first anchorage.