This brake master cylinder is precision-engineered to match the design, function, and performance of the original master cylinder on specific vehicle years, makes and models. Brake Master Cylinder. This part generally fits Mazda vehicles and includes models such as CX-9 with the trims of Grand Touring Sport Utility 4-Door,GS S port Utility 4-Door,GT Sport Utility 4-Door,Sport Sport Utility 4-Door,Touring Sport Utility 4-Door.