I am selling this because I haven't used it at all. Please see below for details. Shipping will be around the end of August, so please make your purchase around that time. The SmallRig Seamless Focus Gear Ring Kit 4185 fits perfectly on DSLR and mirrorless camera lenses and is compatible with follow focus systems. The kit is equipped with standard 0.8 MOD 62.5-64.5mm/66-68mm/69-71mm/72-74mm gear rings. Made of environmentally friendly rubber material, it can be stably fixed to the lens by elastic deformation, achieving a 360° seamless fit to the lens. The AB stops can be freely attached to any position on the lens by the barb, providing a physical limit for automatic lens movement calibration of DSLRs and micro-sensitive lenses with wireless follow focus. It also has low rotational noise and can be used with the Mini Focus 3010 series and Modular Focus 3850, which provide a 360° seamless fit for accurate focusing. Key Features 1. 360° seamless fit and unlimited zoom. 2. Adjustable A/B stops for lens auto-calibration. 3. Standard 0.8 MOD, non-slip surface design, accurate conduction. 4. Stretchable and easy to install. Compatibility 1: Standard 0.8 MOD gear or follow focus. 2: Please refer to the lens model list for lens compatibility. Included Items Φ62.5-Φ64.5mm Seamless Focus Gear Ring + A/B Stops x 2 Φ66-Φ68mm Seamless Focus Gear Ring + A/B Stops x 2 Φ69-Φ71mm Seamless Focus Gear Ring + A/B Stops x 2 Φ72-Φ74mm Seamless Focus Gear Ring + A/B Stops x 2 Thank you for looking.