Buy from Amazon : http://www.amazon.com/gp/product/B006QHWYC8?tag=scratchandsti-20

Lanparte Follow Focus for Hd Video Cameras

Mode FF-02 With quick block and release clamp
Applying for 15mm rods film industry standard Can support modulus of 06 07 or 08 gears
Dovetail groove design makes sure the follow focus wont shake when be using Cooper gear and precision bearing solid and durable
Pure cooper helical gear provide close integration and precision operation High density Damping Greases offer you comfortable and easy use
Can easily adjust the follow focus to fit for different size lens Joints of standard design facilitate connecting with focus whip and rocker