KKmoon Wireless Strobe Siren standalone Alarm for GSM Home Security Alarm System 433MHz Work as a standalone alarm host or wireless siren. 20 wireless defense zones. At most 5 wireless remote controllers. Alarm with both voice prompts and quick flash strobe. Wireless learning codeadding new accessories, convenient , safe and efficient One-key-control function: Remote control to Arm/emergency alarm/disarm Built-in rechargeable Lithium battery. Smart screw and mount base.