This age-old accessory screws onto the master cylinder in place of the cap, effectively increasing fluid capacity by about 20%. With the demise of the tall reservoir "S" master cylinder, this is the only way to regain that safety margin of a little more fluid!
If you are using any of the master cylinders other than the latest dual master, you have a small reservoir for brake fluid. This "Special Tuning" designed piece is easy to install and provides a little added insurance. Not only does it add some fluid to the reservoir, but the see-thru design allows for visual inspection of the level with out removing the cap!
Installation is as simple as unscrewing the stock cap, screwing the extension on, topping up the fluid, and replacing the cap.
This will NOT work with any plastic reservoir master cylinder.