This is a pair of Trailer Leaf Springs rated to 5,800lb Capacity Total, or 2,900lb capacity each. Leaf springs should always be replaced all at once, so we offer this pair of springs to make replacing them easier. The Double Eye Style of Trailer Leaf Spring requires (3) 9/16" or 1/2" diameter (the pre-installed bushings are 9/16" ID) Bolts to install to your trailer. The hardware is not included with this set of springs.