Sigma 17-70mm F2.8-4 DC HSM Contemporary Lens with UV, CPL, FLD, ND4,+10 Macro Filters and Bundle for Pentax K-S1, K-500, K-50, K-30, K5 IIs, K-7, K-5, K-3, K-2, K-X, K20D, K100D, K110D and K10D Digital SLR Cameras This lens is part of Sigma's Contemporary line deeming it lightweight and compact while still exhibiting high optical performance. Large aperture high-speed lens ideal in low light Two FLD (F Low Dispersion) glass elements, one SLD (Super Low Dispersion) glass element, and three aspherical glass elements Maximum magnification of 1:2.8 and a minimum focus distance of 8.7" HSM (Hyper-Sonic Motor) ensures a quiet and high-speed auto focus