This compact motion sensor will detect anyone who attempts to enter the protected area. A loud 90 db alarm siren will sound off to scare the intruder away and alert others to pay attention to the motion detected event. It can be fixated on the wall or simply put it on the desk or hand carry it. This motion sensor alarm is powered by AAA batteries or using AC power adapter. This device can also be used as a door window entrance alert chime for retail stores, office or warehouse area. Or users may set it up at camp site as the watchdog for all purposes. Portable Personal Alarm The motion-activated alarm is great to be used at home for nursing care such as alerting parents if young children wander off into an area that might be hazardous such as a hot BBQ table, pool, etc. 3 Operation Modes This motion alarm unit has a mode switch for selecting between 3 different operation mode as needed: Alarm Mode: The alarm siren will sound off for 15 seconds with flashing red light once movement is detected but the siren sound volume can not be adjusted in this mode. Voice Mode: This motion alarm will play "dingdong ,hello, welcome" in human voice with flashing red light. The volume can be adjusted to desired level. Music Mode: It will be playing the selected one out of the 32 songs programmed into the alarm. Users can adjust the volume level using the volume button. Dual Power Supply Choice This indoor motion sensor alarm can be powered by 3 AAA batteries or powered directly through using a AC power adapter with DC output between 9V and 15V as well. Wide Detection Range Its infrared detection range for horizontal angle is 110 degree with 20 ft in vertical range.