The dedicated 1.4x APO Teleconverter features a high performance 5 element/3 group optical design, and it is optimized for use with long telephoto and telezoom lenses.The high performance optical characteristics of these teleconverters maintain the optical performance of the compatible lenses with which they can be used. Sigma APO Tele Converter 1.4x and 2x are dedicated Tele Converter lenses, which should be used only with the listed lenses. The 1.4X Convertor will fit the following lenses 180mm f/3.5 APO MACRO EX HSM - MF 300mm f/2.8 APO EX HSM - AF 300mm f/4.0 APO MACRO - MF 400mm f/5.6 APO MACRO /HSM - MF 500mm f/4.5 APO EX HSM - MF 800mm f/ 5.6 EX HSM - MF 70-200mm f/2.8 EX HSM - AF 70-210mm f/2.8 - MF 50-500mm f/4-6.3 APO - MF 100-300mm f/4 EX HSM - AF 120-300mm f/2.8... Less

Sigma 70-200mm F2.8 EX DG APO Macro HSM II Lens Kit for Pentax Includes Professional 3 Piece Filter Kit 3 Piece Deluxe Cleaning Kit 4" Travel/Tabletop- Tripod Universal Lens Cap Keeper Designed for use with full frame digital SLR cameras. May also be used with smaller APS-c size sensors with a corresponding effective increase in focal length to about 100 to 300mm with most cameras HSM (Hyper-Sonic Motor) ensures a quiet & high-speed auto focus Minimum focusing distance of 39 inches & high close-up capabilities with a maximum magnification of 1:3.5 Extremely compact design weighing only 48.3 ounces & measures only 7 inches in length A lens hood, front & rear lens caps and carrying case are included with the lens. This product has a 1 year Limited warranty. Sigma's APO 70-200mm F2.8 II EX... Less

The high performance DA* 300mm ED (IF) lens incorporates an SDM system which creates a smoother, quieter auto focus. Featuring a Quick-shift Focus System, switching from auto focus to manual is instantaneous. Weather and dust resistant, it's the perfect lens for extreme weather conditions. Developed specifically for PENTAX digital SLRs, the DA* 300mm ED (IF) SDM lens has PENTAX SP coating which protects the exposed lens elements, and a focal length equivalent to 450mm in the 35mm format.

The high performance DA 300mm ED (IF) lens incorporates an SDM system which creates a smoother, quieter auto focus. Featuring a Quick-shift Focus System, switching from auto focus to manual is instantaneous. Weather and dust resistant, it is the perfect lens for extreme weather conditions.

16MP, 1080 Video, 3" LCD, Weather Sealed advanced 11-point AF engine with new optics , top-of-its-class weather seals make it resistant to water, fog, snow, sand, and dust,cold-proof down to 14 degrees Fahrenheit