Abstract: The invention relates to a part (1) including a structural portion made of an electrically insulating or low-conductive composite material (2), such that a piece containing glass fibres or carbon fibres is protected against the accumulation of electric charges or impact from lightning by a metallisation of the surface to be protected. The metallisation includes a screen (31) of an electrically conductive material covered with a layer of an electrically conductive paint (32). A sizing and priming layer (33) is also provided between the screen and the conductive paint, as well as a finish paint covering the conductive paint (32). The assembly results in a protection against impacts from lightning with a reduced size as compared to traditional metallisations with a metal screen.