An interconnector element for connecting two electrical installation boxes (501, 502) to each other, the interconnector element comprising: a body part having a first dimension extending in a first direction, a second dimension extending in a second direction, and a third dimension extending in a third direction, the first direction, the second direction and the third direction being perpendicular to each other; and first connection means provided in the body part, and adapted to connect a first electrical installation box to a second electrical installation box in a first relative position in which there is a first distance between centre planes (cp501, cp502) of the first electrical installation box and the second electrical installation box, the first distance being parallel to the first direction, the first connection means comprising a first connector member adapted for co-operating with box connection means of the first electrical installation box, and a second connector member adapted for co-operating with box connection means of the second electrical installation box, characterized in that the interconnector element comprises second connection means provided in the body part, and adapted to connect the first electrical installation box to the second electrical installation box in a second relative position in which there is a second distance between centre planes (cp501, cp502) of the first electrical installation box and the second electrical installation box, the second distance being parallel to the second direction, the second connection means comprising a third connector member adapted for co-operating with the box connection means of the first electrical installation box, and a fourth connector member adapted for co-operating with the box connection means of the second electrical installation box, the second distance being unequal to the first distance. a body part having a first dimension extending in a first direction, a second dimension extending in a second direction, and a third dimension extending in a third direction, the first direction, the second direction and the third direction being perpendicular to each other; and first connection means provided in the body part, and adapted to connect a first electrical installation box to a second electrical installation box in a first relative position in which there is a first distance between centre planes (cp501, cp502) of the first electrical installation box and the second electrical installation box, the first distance being parallel to the first direction, the first connection means comprising a first connector member adapted for co-operating with box connection means of the first electrical installation box, and a second connector member adapted for co-operating with box connection means of the second electrical installation box, characterized in that the interconnector element comprises second connection means provided in the body part, and adapted to connect the first electrical installation box to the second electrical installation box in a second relative position in which there is a second distance between centre planes (cp501, cp502) of the first electrical installation box and the second electrical installation box, the second distance being parallel to the second direction, the second connection means comprising a third connector member adapted for co-operating with the box connection means of the first electrical installation box, and a fourth connector member adapted for co-operating with the box connection means of the second electrical installation box, the second distance being unequal to the first distance.