Made of Billet 6061 Aluminum and TIG Welded with Billet Aluminum machined fittings for a proper fitting seal. These tanks were designed with racers in mind to get down the track safely, by sending your overflowing coolant to this tank and not the ground, while still maintaining your windshield washer functionality. This is a combination coolant tank and washer fluid tank for your GTR! Perfect to save space and improve engine bay looks!