The invention relates to a connection block with means for retaining a conductive rod (8), wherein the means for retaining the rod (8) in the body (2) include at least one hook (13) with a base connected to a bottom wall (7) of the connection block and a retaining end (15) with a retaining surface (16) bearing against one edge of the rod (8) for maintaining the same in the insulation body (2), the hook (13) being mobile so as to be withdrawn when inserting the rod (8) into the housing (9) of the insulation body (2). The hook (13) is capable of rotation relative to the base (13) about a rotation axis that is substantially parallel to the offset direction of the retaining surface (16) relative to the base of the hook (13).