Brembo RSC19 Radial master cylinder 1 inch HD

19 mm piston x 18 - 20 mm ratio ( adjustable ) 

for custom HD 1 inch handle bar 

performance braking , better feel and adjusteble ratio 

reservoir not included , see here for option 44426385

the stock front brake light switch will no longer work, 

a hydraulic switch can be mounted 920852