Our expansion tank catch can combo is great for boosted e36's! It fits in the corner of the engine compartment and allows your charge pipes to run along the chassis rails with out having to compromise fit. They feature a 3/4 barb fitting for the valve cover breather to be plumed into. The coolant side allows a hose to be ran to the radiator hose for filling of the coolant system, as well as a 1/4in fitting for over flow/steam. The expansion tank cap is a 20psi cap.