These are the individual springs and shims sold in our FMRV2SPK kit for our large blow off valve FMDVRAYV2. Please use the table below to find the part number required and then select it from the drop-down list above. *The 4th picture above illustrates the valve assembly, please note that only one shim can be used and how the shim fits between the piston and the spring* Note: Serious or permanent damage may occur to the engine and associated components if this product is incorrectly matched to the individual engine requirements. Forge Motorsport nor any of its Authorised Distributors can assume any responsibility for any adverse effects resulting from the incorrect installation of this product. All Forge Motorsport products come with a limited lifetime warranty. All warranty claims must be accompanied by the original proof of purchase to enable us to help you. Failure to supply this proof will result in your claim or enquiry being denied.