This is for adapting the Chase Bays Single Piston Brake Booster DeleteReservoir for chassis that use the brake master cylinder reservoir as the fluid feed for the clutch master cylinder. IE: BMW, VW, Evolution 6 7 8 9.It can also be used to convert a clutch master cylinder to be a brake reservoir fed design. We have found that this product works great on 92-00 Honda Civic / 94-01 Honda Integra and Nissan 350z / G35 chassis.