The Panasonic DMW-TC20 2x Teleconverter can be attached to the Panasonic Lumix Leica DG Elmarit ES200 lens to increase its f-number to a value two steps higher than the original values. This effectively doubles the lens's focal length from 200mm to 400mm. The teleconverter easily screws to the ES200 so it can be attached and removed quickly and it includes a carrying pouch to protect it when not in use.