The Zacuto Z-FF-E Z-Focus Extender is used to extend the distance between the focus knob and gear housing on any Zacuto Z-Focus. Moving the focus knob away from the rods is essential for compact rig setups with multiple accessories. The Z-Focus Extender is 4.5" long. The added distance provides clearance between an EVF and focus knob, making it much easier for the focus puller or camera operator to control the knob and see focus marks. This accessory can potentially shorten your overall rig length by 3", moving the rig center of gravity closer to the user's shoulder.