Guangzhou Baiduoli is an enterprise specializing in traffic safety alarm development, production and marketing with a registered technology and development limited company in Hong Kong. The two brands of the company have received two registered trademarks; the technology of traffic safety alarm has been granted the national patent (patent application NO: 200620059531.9) and the “Tiandi NO. 1” traffic safety alarm has also been granted the national patent (patent application NO: 200730049827.2). Speed-limit safety alarm, or traffic safety alarm, provide safety warnings for drivers through voice broadcast of road condition (***** dangerous sections and speed limits). Generally overspeed points are detected in dangerous sections with frequent accidents and punishments include penalty, mark deduction and driving licenses suspension, etc. Our voice warnings help ensure drivers’ safety by reminding them of driving safety. The product receives signals by means of the earth reference coordinates provided by the 24 synchronous satellites launched by the American NASA and SF3 standard receiving module (American patent) and transformed latitude-longitude coordinate values to realize positioning and driving safety warnings. The embedded car dual-chip microwave signals receiver receives signals of Doppler radars and speed-measuring laser guns and gives timely warnings. It early warns most police Doppler radars of the world. Imbedded with high-capacity lithium batteries and antenna, the GPS satellite positioning speed-limit safety alarm is your best assistant for safe driving and traffic tickets reduction