Tokina ATXAFM100PRON 100mm f/2.8 Pro D Macro Autofocus Lens for Nikon AF-D, Black Manufacturers 3 Year Limited USA Warranty card is included in the box. For all repairs, USA warranty card and an authorized USA retailer's sales receipt must be sent together. The AT-X 100 PRO D also has a very convenient focus limiter switch. Toking's exclusive One-touch Focus Clutch Mechanism. 55mm non-rotating filter thread for use with macro ring flashes and special effects filters. min. focus distance-0.30m (max. magnification ratio 1:1)