This is an Edelkrone Slider Plus+ in very good condition - looks almost new. It has a range of about 10" of travel on a table top to about 20" when mounted on a tripod. It has the spot in the center you can "feel" as many of these models do but we had no trouble making smooth moves with it. Very high quality, well constructed slider with adjustable feet. Comes with original box. Please click the link below for more info. Thanks for looking.
http://www.ebay.com/itm/301251461169?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
http://www.ebay.com/itm/301251461169?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649