Clamping levers are designed to restrict the clamping movement to not exceed the maximum clamping force. These units are constructed with eccentrical cam, allow torque free clamping action. There are no loose parts on the unit, as all components have been precisely placed on the unit, and connected to each other. Distances between the clamping surface and the lever cams can be adjusted on the planar curve, which will allow the clamping position to be established with little effort, using the maximum clamping force. The lever position in relation to the clamping axis can be established.