Bosal are manufacturers of exhaust systems and towbars their products are supplied as original equipment to most car manufacturers throughout the world brand bosal part exhaust pipe reference 852 317 technical specification fitting position front engine code z1 4xep engine code z1 4xep opel astra g hatchback 1 2 16v 2000 2005 75hp 1199cc opel astra h 1 4 2004 90hp 1364cc opel astra h estate 1 4 2004 90hp 1364cc vauxhall astra mk iv 1 4 16v 1998