Minoura RDA-2429 D Bicycle Trainer - 400-5960-00 World's only one-rim drive unit, driven by rubber roller contacting rim side wall No-vibration ride no matter the tire tread, even for knobby MTB tires Seven levels of resistance Fits any wheel size between 24 inch and 29 inch/700c; 35 mm diameter legs provide stability while supporting weight 25.6D X 20W X16H (inches)