The huge variety of springs we make is added to the site to help Ultra High Range Damper customers to freely swap springs to tune their ride's compression stiffness, while the UHRAD adjuster controls rebound with any spring you choose on the list. Choose your spring rate, overall length, and color choice in the dropdown menu below. **NOTES: Springs shorter than 6" must use helper springs sold separately. If you are putting 20KG plus on a McPherson strut car like S13 & BRZ, you will need helper springs. This will make sure you're not topping out your shocks, which will damage the shock. However, 20KG+ can be used on a big body Lexus and other double wishbone cars without helper springs. Helper springs are recommended whenever they can fit your coilover, because it helps static ride height exist in the middle of shock travel, therefore helping the wheel droop out while traversing driveways & also helps dial in the compression travel bump stops. You can buy our progressive micro cellular foam bump stops separately to achieve a safe suspension travel that is comfortable on its initial approach to end of travel. ***Copper and gold spring coating color varies by batch & available inventory but you can still enter in your preference. Contact us if you're unsure of compatibility with your vehicle.