Opteka 650-1300mm f/8 HD Telephoto Zoom Lens for Pentax K-1, K-3 II, KP, K-70, K-S2, 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 Manual focus telephoto lens compatible with full-frame sensors as well as APS-C sensors 8 Lens elements in 5 groups, low-dispersion multi-coated HD optical glass to reduce flare Great for the wildlife or nature photographer who wants to be hidden while taking photos of the subject Built-in tripod collar for improved lens balance Newly improved 2017, digitally-optimized telephoto zoom lens