This is impossible to put together.  I haven't been able to use it.  Thought I was trying out something which might help improve my fitness, but the cheap price and free shipping is useless.  Can't put it together.  Pay a bit more, or better yet, go to a sportshop and get one that is pre-assembled.  Try it out to make sure it will be sturdy and usable.  I couldn't do that because I live 50 miles from the nearest such store. Do it, if you want something like this.  Don't gamble on a mail order cheapie.