*Although Bio-Syn EHC FLUID has been proven to be compatible with phosphate ester fluid in good condition; it is strongly recommended that systems designated for conversion be drained as much as possible, and if necessary flushed, in order to derive the maximum benefits from the fluid change out. 

Bio-Syn EHC FLUID does not create phosphoric acid nor does it create any type of aggressive acid.  The typical total acid number of Bio-Syn EHC FLUID is less than 1 and represents a safe organic type of fatty acid, which is not harmful to the skin, as can be the case with phosphate ester fluid.