Castrol SRF Racing Brake Fluid is an ultra high performance brake fluid and popular with the highest performing teams in the world. The key to Castrol SRF brake fluid's superior performance is its silicon ester technology. Less hygroscopic then typical fluids (ie, absorbs less water), Castrol SRF also reacts chemically with the absorbed water to reduce its adverse effects creating an industry unheard of 518°F (270°C) wet boiling point! Exceeds SAE 1703, ISO 4925, JIS K2233, FMVSS No. 116 DOT3 and DOT 4 specifications.