We just put on an a frame that my husband built from railroad ties.  It is very sturdy and seems like it will be a lot fun.  We got it for my 7 year old granddaughter and I needed to push her on it.  She has to get used to pumping it by herself.  We felt it was a lot of money but it was made well.  The harness that was included so you attach it was not so great.  We have to buy different hinges to get the most availability.