A mural electrical apparatus has a metal mounting bracket, a sub-plate, a plate fixed to the sub-plate by a local link, this plate bearing or constituting a conductive portion. This apparatus further has an elastic conductive member provided at least with an orifice, a flexible arm, and a flexible arm, this member being secured to the sub-plate by the local link, crossing the orifice, and the flexible arms protruding in opposite directions to elastically respectively press against the conductive portion and against the bracket, the conductive portion thus, being brought to the same electric potential as the bracket.