Ultimate-match front coil shock springs for pan car front suspension offer an additional range of choices to fine-tune your car. Powder color-coded for quick & easy identification. Black color. Set of 2. Developed through extensive testing and racing experience. Stiffness is controlled by the thickness of the wire and also by the number of coils; softer springs have a lower ''C'' value, while stiffer springs have a higher ''C'' value.