The Nikon Auto BR-4 Ring Reversed Lens Aperture Opening Adapter is a versatile accessory designed to allow reverse mounting of compatible Nikon lenses for macro photography. This adapter features a precise aperture opening control to adjust the amount of light entering the lens, ensuring optimal exposure settings. It is crafted by Nikon, a renowned brand in the photography industry, guaranteeing high quality and compatibility with Nikon lenses. The Nikon Auto BR-4 Ring Reversed Lens Aperture Opening Adapter is a must-have for photographers looking to explore the world of macro photography and capture stunning close-up shots with their Nikon lenses.