Vintage Tamron 2x Teleconverter Camera Lens with Pouch Nikon

This is the magnificent Tamron 2x Teleconverter specifically the AF BBAR MC7 model, made in Japan, designed for Nikon F-mount lenses. Key features and information: It doubles the focal length of a compatible lens. For example, a 300mm lens becomes 600mm. It reduces the amount of light by two f-stops. It is compatible with most lenses that do not have a protruding rear element. It features a seven-element optical design and specialized coatings to reduce flare and ghosting. It can be used with Nikon AF-D lenses. The physical dimensions are 1.73 x 2.72 x 2.72 inches.