This is a high pressure oil pump for the T444E International trucks with engine serial number 843990 & up. It is manufactured by Bosch and sold on an exchange basis. This requires that the old high pressure pump core must be returned. CORE CHARGE: A core charge of $250.00 will be applied to your credit card account, if the core is returned within 30 days you will receive credit. Feel free to call our parts department at 800-891-8038 with any questions.