horn driver unit: 1.CE &ISO9001 certificate 2.IP rating: IP66 3.aluminum body,sound is strong 4.OEM service HORN Driver UnitModel : P-500FRated input : 50WImpedence : 16 ohmFrequency response : 180-7000HzS.P.L. (1w/m) : 112 dBVoice coil: 51.6KSVDimension : 120 * 110 mmproducts has obtained BV certificate , CE ,ROHS ,ISO9001 . Packing : outer Carton inner box.12pcs/ctn ,can supply OEM service.