Metabones Nikon F to E-mount/NEX (Black Matt) II Both camera-side and lens-side of the adapter are made of brass, precision-machined and plated with chromium. Satin surface finish - just like your OEM lens and camera mounts. Precise fit and solid connection - lens has no play, gap or wiggling when mounted on adapter and no adjustments are required to fit your lens. Designed to reach infinity focus while maintaining the correct registration distance required to maintain optical quality of CRC lenses or lenses with floating elements.