The Sigma 1.4x Teleconverter EX APO DG for Canon is a third-party teleconverter for use with compatible telephoto lenses. Key features include:

1.4x Conversion. The Sigma 1.4x Teleconverter EX APO DG extends the focal length by 1.4×. With the increase in focal length, you’ll reduce the maximum aperture by one stop.

High-Quality Optics. It features an apochromatic lens design through the use of Sigma’s special low-dispersion glass elements, providing images with high color accuracy and minimum optical aberrations. It also has Sigma DG multi-layer coating that cuts down on ghosting from internal reflections.