The new Mark III system provides a high quality follow focus system to maintain high cost performance. Applicable models: All DSLR Cameras, Camcorders, Compatible Lens Cameras Camera: Sony A7 Series, (A7, A7R, A7S), A7II Series (A7II, A7RII, A7SII), Panasonic GH3 / GH4, Black Magic BMPCC, Canon5DII / 5DIII / 5DIV, Nikon D500, etc. Camcorders: Blackmagic BMPC / URSA mini, Sony FS100 / FS700 / FS7 5 / FS7 Compatible with industry standard 15mm rods such as / F55 / F5 / F3, RED SCARLET / EPIC / RAVEN / ONE, Kinfinity KineRAW / KineMAX etc. Rail Distance: 23.6 inches (60 cm), Rail Diameter: 0.6 inches (15 mm), Weight: 12.8 oz (340