Sigma Used 170-500mm f/5-6.3 APO

This lens uses one aspherical lens and three SLD(Special Low Dispersion) glass elements for excellent correction all types of aberration, making high-quality images a reality throughout the entire zoom range. The five-group zoom and rear focus systems ensure high performance ...This lens uses one aspherical lens and three SLD(Special Low Dispersion) glass elements for excellent correction all types of aberration, making high-quality images a reality throughout the entire zoom range. The five-group zoom and rear focus systems ensure high performance stability and ease of use.

Since the front of the lens does not rotate, a circular polarizing filter can be easily attached and use.