CHP-109 is a pair of Juvenile Standard Single Spring Platform Rocker Springs. This item comes as a pair, one for each side of the rocker platform. For one one rocker, you only need one set. Please note that these springs are made for a child's chair and are not suitable for an adult sized rocker. The spring is 8 Gauge (8 Turns) and is made of steel. Wood screws are provided. The base is 3-1/4"long by 2-1/2"wide.