Features:Exact follow focus design helps to adjust focus.Damping design， good touch feeling. Convenient for assembling and disassembling.Easy to be upgraded.Follow focus is made of high strength aluminum alloy.Gear drive can be mounted on both sides (works for both right-handed and left-handed).With a focus ring， it fits lens size from 52mm to 86mm.International standard， mounts on 15mm rod support (rail center to center: 60mm).Specifications:Compatibility: All (D)SLR cameras and camcordersMaterial: Aluminum alloy + PC + ABSFit lens size: 52-86mm / 2.0-3.4inFit rail distance: 60mm / 23.6inFit rail diameter: 15mm / 0.6inWeight: 341g / 12.0ozPackage size: 18 * 9.3 * 9.3cm / 7.1 * 3.7 * 3.7inPackage weight: 400g / 14.1ozPackage list:1 * Follow focus1 * Focus ring