The two new SIGMA TELE-CONVERTERs TC-1411 and TC-2011 are designed exclusively for use with SIGMA's mirrorless camera lenses. The superior optical performance of SIGMA lenses in the Contemporary, Art and Sports product lines is the result of SIGMA's commitment to the highest image quality. The SIGMA TELE-CONVERTER TC-1411 and TC-2011 preserve to a high degree the image quality of the lens while extending the focal length. Mounted between the lens and the camera body, the TC-1411 increases the focal length of the camera by 1.4 times and the TC-2011 by 2 times. The new teleconverters are also designed to be dust- and splash-proof, comparable to the lenses in the Sports line, and thus allow use under harsh conditions in conjunction with dust- and splash-proof camera bodies and lenses. Tele-converters are easy to use and provide an affordable alternative to a larger, more expensive telephoto lens, providing an "UltraTele" angle of view with compatible telephoto and macro lenses while maintaining the performance of the combined lens.