Completely gear driven design for slip-free and accurate movement - Quick release mounting design - Adjustable A/B hard stop * Gear drive can be mounted from either side (works for both right and left-handed) - Improved design has less dampening which gives virtually zero backlash (-- Long-life precision engineered gearbox enables accurate and reliable focusing * Mounts onto 15mm Rod Support (60mm center to center difference) - Compatible with all DSLR cameras, video cameras * Compatible with industry standard 15mm rods - Comes with one adjustable standard 0.8mm pitch flexible gear belt * Gears nylon and ABS -- Dial Index Adjustment : 360° -- Fit Rail Diameter : 15 mm -- Fit Rail Distance : 60 mm -- Gear MOD: industry standard 0.8