Sigma 876110 APO 2x EX DG Teleconverter - Sigma SLRExtend Your Reach with Optical Precision The Sigma APO Teleconverter 2x EX DG is a high quality optical accessory designed to double the focal length of your Sigma SA mount lenses. This teleconverter maintains image quality while providing extended reach for capturing distant subjects. Specifications: Brand: Sigma Model: 876110 Compatibility: Sigma SLR Cameras with Sigma SA Mount Magnification: 2x Type: APO Teleconverter