Panagor Auto 2x Teleconverter

This Panagor Auto 2x Teleconverter fits the Canon FD mount. A teleconverter is a gadget that fits between the camera body and lens to magnify the image made by the camera, so a 200mm lens using a 2x teleconverter will become a 400mm lens for example. But this comes at a cost, a 2x teleconverter brings a 2-stop reduction. So if you use an F2.8 lens it will become a F5.6 lens.