These coil-over springs are manufactured from the highest quality chrome spring steel available. Each spring carries a 100% guarantee. If any spring is found to be defective in material or workmanship, it will be replaced at no cost to the purchaser. Suspension Spring Specialists offers the largest selection of heights and rates of springs available. These springs are ground flat on both ends and each spring is tagged with the rate. "WARNING: This product contains a chemical known to the State of California to cause cancer and birth defects or other reproductive harm."