Fotga 18" Flexible Whip Speed Crank for Follow Focus FF 12mmx12mm The FOTGA DP3000 whip speed crank can be attached in the provided square hole at the center of the wheel in the follow focus. Thus, the hand merely has to spin the rod, which turns the wheel The micro whip allows the user to adjust focus remotely significantly reducing the risk of vibration being picked by the camera Made of the material as heat-shrink tube and aluminum, this Fotga brand speed crank whip is strong enough and touch good. Diameter of the blue hand wheel is 42mm,and the proper ergonomic design on the wheel makes it easy on using. And it fit for any follow focus with standard accessory port (size:12mm x 12mm) Safety-look design at the end of termination, which ensure is not fall off the follow focus Length:18" Connector size: 12mm x 12mm Color: Black