This attachment allows a rigid frame wheelchair user more mobility on uneven surfaces such as grass and gravel. It raises the small front wheels off the ground and creates a "three-wheeler". No more worry about the little front wheels of the wheelchair getting stuck in ruts or hitting small rocks and coming to a sudden stop!! This attachment allows the user to smoothly go over any terrain (rough or smooth). It is in excellent working condition and I am only selling because I have a different wheelchair now. The tire on the FireWheel is inflatable. An adaptation is available to use this attachment on a regular folding wheelchair.