The Beringer Aerotec CRO9 Master Cylinder is CNC machined from billet aluminum and then anodized for an attractive finish. It's a great upgrade for improved clutch feel and easier lever modulation. Radial mounted Ø14.5mm piston is 40% more efficient with radial orientation. Ball Bearing-Mounted Lever means less hand effort and higher precision feel. Integrated fluid reservoir is less prone to crash damage, unlike remote reservoirs. Multiple colors available; - Anodizing - Black, Blue, Gold, Green, Orange, Purple, Red, Silver, Titanium.- Plating - Nickel, Chrome. FLUID COMPATIBILITY: The internal seals are safe to use with DOT4 racing brake fluid and mineral oil. NOT compatible with DOT5 brake fluid.***Brake fluid is preferred as it does better with higher heat so it can provide a more consistent feel as a result. If your bike came with a mineral oil system, you cannot change to brake fluid unless you change the slave cylinder as well. We recommend the Oberon clutch slave cylinders.*** BIKE COMPATIBILITY: The CRO9 is great for larger displacement motorcycles. If you have a smaller displacement bike, like a 250-500cc supermoto, we recommend the smaller CRO8 which has 12.7mm piston.