The Twinsoft spring combines two Simmons suspensions: Duetto and Sensoft Evolution. The combination of these technologies provides exceptional feel. The upper suspension, Duetto, perfectly conforms to the body's shape for optimal comfort. The lower suspension, Sensoft Evolution, gradually absorbs body pressure and evenly distributes weight. The sleeper feels supported and cared for gently. The Sensoft Evolution spring is wider at the bottom and therefore ensures perfect spring stability and fits the No Flip® system.