Neewer Easy Zoom Focusing Adjustment Follow Focus Metal Handle Scale Lever with Gear Ring for Camera Lens Small and light, easy installation to camera lens / follow focus at DSLR Rig System Facilitate adjustment, easy zooming / focusing Can be applied as FOCUS LEVER + ZOOM LEVER with another lever Gear ring included, more facilitated to control the follow focus and camera lens Scale lever included, fix it on the camera lens, you can read the angle the lever you adjusted there