Part Number BM91684HK. OPEL 25195105, 55574237, 55597325. VAUXHALL 25195105, 55574237, 55597325, 850112, 865004. Unique approval number for each BM part number. Type Catalytic Converter. It works by converting exhaust emissions into less harmful ones when the gasses pass through it, triggering a chemical reaction.
