Connection terminal for connecting an electrical conductor, comprising an insulating material housing having at least one conductor clamping device which is designed such it can be operated by a respective operating element which is mounted in the insulating material housing pivotably about a shaft, wherein the conductor clamping device comprises a clamping point for the electrical conductor, which clamping point is formed by a contact element arranged fixed in position in the insulating material housing and a clamping spring arranged movably between an open position and a clamping position in the insulating material housing by means of the operating element by way of a free limb of the clamping spring being connected in an articulated manner to the operating element via a connecting element, so that the clamping spring is moved to the open position with application of a tensile force via the connecting element by means of a pivoting movement of the operating element in a first direction and to the clamping position by means of a pivoting movement opposite to the first direction, wherein the operating element comprises an articulation element radially spaced apart from the shaft centre of the said operating element and designed for connection of the connecting element in an articulated manner, wherein the articulation element is arranged on the operating element in such a way that the lever arm formed by the articulation element and the shaft centre, in the open position, is oriented at least substantially parallel to the direction of the tensile force acting on the free limb of the clamping spring by means of the connecting element, so that the lever arm formed by the articulation element and the shaft centre in the open position differs from the parallel by an angular value of less than 10°, characterized in that the connecting element comprises a flat support region which engages over the articulation element, so that the articulation element is formed displaceably relative to the support region, wherein the flat support region is arranged at a right angle to a connecting section of the connecting element. an insulating material housing having at least one conductor clamping device which is designed such it can be operated by a respective operating element which is mounted in the insulating material housing pivotably about a shaft, wherein the conductor clamping device comprises a clamping point for the electrical conductor, which clamping point is formed by a contact element arranged fixed in position in the insulating material housing and a clamping spring arranged movably between an open position and a clamping position in the insulating material housing by means of the operating element by way of a free limb of the clamping spring being connected in an articulated manner to the operating element via a connecting element, so that the clamping spring is moved to the open position with application of a tensile force via the connecting element by means of a pivoting movement of the operating element in a first direction and to the clamping position by means of a pivoting movement opposite to the first direction, wherein the operating element comprises an articulation element radially spaced apart from the shaft centre of the said operating element and designed for connection of the connecting element in an articulated manner, wherein the articulation element is arranged on the operating element in such a way that the lever arm formed by the articulation element and the shaft centre, in the open position, is oriented at least substantially parallel to the direction of the tensile force acting on the free limb of the clamping spring by means of the connecting element, so that the lever arm formed by the articulation element and the shaft centre in the open position differs from the parallel by an angular value of less than 10°, characterized in that the connecting element comprises a flat support region which engages over the articulation element, so that the articulation element is formed displaceably relative to the support region, wherein the flat support region is arranged at a right angle to a connecting section of the connecting element.