DO NOT BUY THIS TREADMILL! After spending hours putting it together (with some pieces that don't quite fit together) I started the treadmill only to find out that one of the belt rollers had fallen down about 3 inches. After opening up the front, I was able to fix it. Now that it's running, the thing is so jerky that I don't feel safe walking, much less running, on it. If it's that jerky with someone at 140 lbs, I feel really bad for anyone heavier trying to use it. This treadmill is flimsy and unsafe. SAVE YOUR MONEY, SAVE YOUR TIME AND DON'T BUY THIS TREADMILL!!