The Vivitar Auto 2x Custom Tele-converter Model 2x-3 is a high-quality teleconverter lens made in Japan. Designed for use with Vivitar lenses, this 2x converter offers manual macro focusing and is compatible with Canon FD mounts. With a maximum aperture that depends on the lens used, this teleconverter is ideal for photographers looking to capture precise details and enhance the focal length of their lenses. Made by Vivitar, a trusted brand in optics, this teleconverter is a reliable and versatile accessory for photography enthusiasts.