Volvo brake fluid is the only brake fluid tested and approved by Volvo Cars. Volvo brake fluid must not be mixed with other unknown brake fluids. Brake fluid has a low viscosity at low temperatures which results in faster response and improved safety in cars equipped with ABS and ESP systems. The product also protects well against corrosion in the closed brake system. Brake fluid is hygroscopic (moisture absorbing). In order for the brake fluid not to absorb moisture during transport and storage, the fluid is supplied in a sealed metal container filled with nitrogen gas at the top. Always keep the brake fluid in this container and seal the lid well. Once opened, use within two months.