We have a factory(ningbo wanming electronics co. Ltd) manufacturing alarms, horn speakers, piezo siren, battery back-up siren and electronic siren. These products are widely used in security system(esp. Car& motorcycle). WB21 Specification: POWER :10/15/20W IMPED.:DC6ohm BATTERY:Ni-Cd 6V 60mA VOLTAGE:DC6-12V CURRENT:600/1200mA SOUND:1 OR 6 TONE dB/M:112/115/120AdB MATERIAL:ABS COLOR:BLACK PACKING:100PCS/0.05CBM