An interconnector element for connecting two electrical installation boxes 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 (dst1) between centre planes (cp501, cp502) of the first electrical installation box and the second electrical installation box , the first distance (dst1) 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 (dst2) between centre planes (cp501, cp502) of the first electrical installation box and the second electrical installation box , the second distance (dst2) 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 (dst2) being unequal to the first distance (dst1). 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 (dst1) between centre planes (cp501, cp502) of the first electrical installation box and the second electrical installation box , the first distance (dst1) 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 (dst2) between centre planes (cp501, cp502) of the first electrical installation box and the second electrical installation box , the second distance (dst2) 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 (dst2) being unequal to the first distance (dst1). <EOS>