The follow focus allows an easy but precise tracking of the focus when filming with DSLR cameras. The gear ring can be mounted to any lens and therefore completes the follow focus system. The focus wheel of the system is equipped with a white surface allowing you to mark and reproduce the focus area. The Follow Focus can be mounted to all video rigs with a rod diameter of 15mm on both sides and comes with an accessory adapter for flexible whips and crank levers ideal for use by a camera assistant. Features: For Camcorders & DSLRs Smooth, Precise Focusing Gear-driven Design Rail Distance: 60 mm Rail Diameter: 15 mm Dial Index Adjustment: 360 degrees Gear Module: Industry Standard 0.8 Easily switchable to either side of camera Constructed of high quality, machined aircraft-grade aluminum Lightweight design Color: Black Package Include: 1X Focus Follow Finder F0 1X Matching Gear Belt 1X Metal Bracket Buy in confidence: One year warranty 7 days 24 hours customer service Quality Check before the items are shipped, saving your time!