These Wilwood master cylinders are know for their quality and reliability. If you're setting up a new hydro or replacing a cheap master cylinder that's blown out, these are always a good option. These are the same master cylinders we use in all of our kits and cars.

This is a 5/8" (.62") bore master cylinder with the integral reservoir. They're typically used for hydro set ups with a dedicated caliper.

The 5/8" bore will have a lighter feel then a larger bore (like 3/4") and a slightly slower action. This is typically good for drift brakes that are hand operated. Most clutches will require a 3/4" bore.