Check the listing for details. ALZO Digital Smoothy Zoom Follow Focus. Condition: New. Listed at 9.88 USD. Works like a follow focus and does not require a rod assembly All Aluminum very lightweight construction Adjustable diameter foam rubber lined metal band firmly grips zoom and/or focus lens rings End wheel finger grip promotes very smooth lens moves Very light; adds almost no weight to the camera The ALZO Smoothy Zoom Follow Focus is a very low-cost that easily attaches to DSLR lens rings and allows for smooth zooms and focus pulls. It is a good replacement for a follow focus at a fraction of the cost. For full lens zooms or deep focus pull actions, this device is superior. It easily covers the full lens ring range without pauses or extreme wrist twists required with a follow focus, and it can produce ultra slow zooms like a pro camcorder. This effect is very difficult to do without a device on the lens ring. The aluminum ring on the end of the arm is designed for a firm finger grip to improve smooth rotation of the lens. This device sets up in seconds compared to a typical follow focus that requires attaching a base plate and rod assembly, which is time-consuming and adds weight. When you want a light, compact, quick and simple solution to produce professional video zoom and focus effects, the ALZO Smoothy Zoom Follow Focus is ideal. Fits lens rings from 50mm to 80mm diameter. Not applicable for really fast (fat) lenses like f-1.4 as these lens rings are too large.