Designed for bikes that already have 12mm banjos…….enables the use of a 10mm banjo bolt through a 12mm banjo fitting (often the black rubber hose types found on late model H/D’s) without having to remove the existing hoses.
NOTE: Joker Machine master cylinders are set-up for the use of the more common 10 mm banjo fittings that bolt onto 3/8″-24 threads in the body.