Castrol React DOT 4 Brake Fluid 1L React Performance DOT4 is a high boiling point brake fluid, designed for use in extreme conditions such as high performance and race vehicles. It is also engineered to cater for continuous stop start driving and hilly terrain, where high brake temperatures can occur. The Aston Martin Works Parts department provides expert knowledge and access to tailor-made and rare parts to a wide variety of trade and enthusiast customers worldwide. We have access to over 100,000 genuine Aston Martin parts and accessories for every Aston Martin model. For Customer Support and Parts Advice please send us a message and we will do all we can to help. Our Parts Department is open Mon - Fri 08:00 - 17:00. Any orders placed outside of these times will be processed the next wor.