Magnet:GM-45 1) Used For:siren,driver unit,speaker ... ,horn speaker 2) Stable,Ferromagnetic 3) ODM/OEM Service 4) RoHS Detailed Parameter of GM-45 ... Manufacturer2) RoHS3) Material:ferrite4) Item Dimensions:45*22*8, Y30 5)Used For : siren , driver unit , speaker ... permanent type3) with powerful magnetic properties4) widely used as speaker&siren&driver unit magnet5) with ...