Febi Bilstein Engine Block Breather Valve - 45181. Quantity Included: 1 - Sold Individually. Weight (kg): 0.034. Please check the item information carefully, as it may contain specific details about this part that will help determine compatibility for your desired application. Failure to do so could result in the incorrect part being purchased. This part is designed to be used as originally intended and not modified for purpose. Please ensure the products are installed by a competent individual. N.B. products are usually supplied without fitting instructions.