The Beringer Aerotec Radial Master Cylinder is CNC machined from billet aluminum and then anodized for an attractive finish. It's a perfect match with the Beringer radial 4-piston caliper. Radial Mounted Piston is 40% more efficient than an axial master cylinder. Ball Bearing Mounted Lever is a stronger mount, requires less hand effort, and offers a higher precision feel. Integrated Fluid Reservoir is much less prone to crash damage, unlike externally mounted reservoirs. Multiple Levers Available #2 - Shortest with 2 finger grab #3 - Mid-length with 3 finger grab and ribs between fingers #4 - Full length with 4 finger grab #5 - Street lever with large inner arch for clearance around switches and 2 finger grab Multiple Finishes Available Anodizing - Black, Blue, Gold, Green, Grey, Orange, Purple, Red, Silver. Plating - Nickel, Chrome. Fits 7/8" Handlebars and clip-ons. Ø20.5mm Piston is sized for use with dual 4-piston calipers. USE DOT 4 RACING FLUID ONLY. (Silicone and other DOT 5 fluid will damage the seals.)