DOT 3 - A regular quality polyglycol fluid. DOT 4 - A refined specification polyglycol fluid as fitted to most faster street bikes now produced. BF307- Brake Fluid compatible with Dot 3 and Dot 4. With stands boiling at higher temperatures than any of the previous formulations. DOT 5 - Silicone fluid as used in Harley-Davidson® Motorcycles and many special High Performance Brake Systems. Combo Pack - Includes 2 each Dot 3,4,5