Focus Camera Sigma 50-100mm /1.8 DC HSM Art Lens or Nikon Mounts w/Accessory Bundle DESIGNED FOR: Designed for APS-C size sensors so that the image circle matches the smaller size of the image sensor of most digital SLR cameras HSM AUTOFOCUS: HSM lenses employ a motor powered by ultrasonic waves that produce a quiet, yet high-speed AutoFocus INNER FOCUS: To ensure stability in focusing, this lens moves the inner lens group without changing the lens physical length BUNDLE INCLUDES: Sigma 50-100mm f/1.8 DC HSM Art Lens / MMC MultimediaCard & SD Secure Digital Reader USB / 82mm 3-piece Fundamental Filter Kit / Focus Lens Cap Keeper / 5 Piece Digital Camera Accessory Kit / 67-inch Lightweight Monopod / Photo/SLR Sling Backpack SIGMA Authorized Dealer - Includes USA Manufacturer's Warranty