AP Auto Teleplus M42 2x Teleconverter

The AP Auto Teleplus M42 2x teleconverter is an optical accessory for compatible cameras and lenses with an M42 screw mount. It doubles the effective focal length of the attached lens, making distant subjects appear closer. This allows photographers to extend the reach of a telephoto lens without investing in a longer lens. As is typical of a 2x teleconverter, this results in a loss of approximately two stops of light. An interesting vintage accessory for users of classic M42 cameras and lenses.