https://www.jumpochina.com/products/bicycle-master-cylinder/ Jinpo bike master cylinders are of omfortable hand feeling, ergonomic design, fine-tune the brake knob for easy adjustment of brake force; Master cylinder in bikes are of expansion and rotation to adapt to different grasping feelings; Quality cylinder of bike is hexagon socket fixed, easy to disassemble and fixed firmly. For more bike brake accessories if you have other inquiries. Bicycle Master Cylinder Technical Specification Are master cylinders universal? The right choice of bike master cylinder can make all the difference in how your bike brakes. It is not a universal fit, because there are different styles and there are different psi levels for disc brakes versus drum brakes.