Restore and enhance your cooling system with the Mishimoto Ultimate Bundle. The Mishimoto Ultimate Bundle includes high-quality upgraded cooling components to replace items we've found to be the most failure-prone. For the 2015-2021 Subaru WRX, we've bundled together our aluminum radiator, silicone radiator hose kit, silicone ancillary hose kit, racing thermostat, aluminum coolant overflow tank, thermostatic oil cooler kit, and titanium turbo blanket.As the stand-out component, our aluminum radiator features full aluminum construction with durable TIG-welded end tanks. This radiator provides a 117-percent increase in coolant capacity and a 34-percent increase in air surface area. These enhancements provide superior heat dissipation and optimal cooling efficiency. To supplement our robust radiator, we've included our incredibly durable silicone radiator hose kit and silicone ancillary hose kit. Mishimoto silicone hoses are constructed from high-grade 4-ply silicone with heat-resistant embedded fibers for superior heat and pressure tolerance. For maintaining low fluid temperatures, we've included our Subaru WRX Racing Thermostat. The Mishimoto thermostat has a lower activation temperature (165.2F) compared to the factory thermostat (190.4F). We've included our all-aluminum, fully TIG-welded coolant expansion tank within our Ultimate Bundle, providing maximum durability during repeated hot and cold transitions. Oil temperatures can begin to rise on vehicles driven aggressively or on track. Because of this, we've included our direct-fit oil cooler kit for the WRX, proven to drop oil temperatures by 20F. Rounding out our Ultimate Bundle is our Titanium Turbo Blanket, explicitly designed to reduce engine bay temperatures and maintain turbocharger efficiency. Time to re-habilitate the cooling system of your WRX with the Mishimoto Ultimate Bundle. As with all our products, this bundle includes the signature Mishimoto Lifetime Warranty.