Eyelids are driven by three controls: upper eyelid soft, lower eyelid soft, eye-spline of eye target. Soft Controls move eyelids up and down, eye-spline bends eyelids to follow the pupil - the result is more natural animation. Weight: spinners set the influence weight of eye-spline to drive Upper: and Lower: eyelids. If the weight is zero then eyelid stays in place while the eyes move. Factor: spinners operate with bending of eyelid bones. If eyelid bones of closed eye are not fit tightly or not line up then you can fix that by these spinners. Bend: spinners operate with rotation of eye bones. Eye bones rotate around different axes and this would create mesh distortion during vertical movement of eyelid, because eye bones may stretch eyelid bones in a given position too much. This distortion shall be removed by Bend: spinners. Small buttons in between the spinners link spinners to each other, if the button is turned on then nearest spinners change values simultaneously.