The Metabones Speed Booster ULTRA Nikon G to Sony E-Mount adapter is a professional optical element designed to unlock the full potential of your full-frame Nikon F-mount lenses on APS-C Sony E-mount cameras. With its advanced 5-element, 4-group optical design incorporating ultra-high refractive index tantalum-based glass, this adapter reduces crop factor from 1.5x to 1.07x while increasing effective aperture by approximately one full f-stop. The 0.71x magnification effectively transforms your lenses: a 24-70mm f/2.8 zoom becomes a 17-50mm f/2.0, and a 50mm f/1.2 lens becomes 35.5mm f/0.9. Precision-machined brass construction with chromatic finish ensures durability, whilst the optical performance delivers improved corner sharpness, reduced distortion, and minimised vignetting across the entire image field.