1. Tone charactor: Siren, manual, wail, yelp, hi-lo, horn, radio. 2. Handhold mike, with controller. 3. Monolithic integrate 1. It conform to national standrad GB8108-1999.2. Tone charactor: Siren, police, fire fighting, wrecker, project, ambulance, guest, low tone antiaircraft, high tone antiaircraft, whistle-1, whistle-2, whistle-3.3. Handhold mike with controller.4. Monolithic integrated ...