2 working modes available for choice: only LED Light flashing or both sound and LED flashing. 3 levels of volume adjustment: High or Medium or Low. 38 ringtones for choose. Receiver working effective range is up to 70 meters. The PIR motion detection distance is 3-7 meters. It can be successfully used for your home, office, store, hotel or other buildings. Ideal for alerting business owners who work in the back or out of sight when customers come in store. It can also be used as a signal when animal is ready to enter or leave. Applications: entry alert, intruder alarm, passageway alarm, bug detector, car alarm (indoor), security monitor warehouse, power supply closet alarm, garage and tool shed monitor, mailbox sensor, front door or walkway detection. Package includes: plug-in electronic receiver, motion detector PIR (power by 3 AAA batteries, NOT INCLUDED); Installation steps: 1. Place the correct batteries (3 AAA batteries) in the sensor, make sure the batteries have been placed in the correct positions. 2. Properly mount the sensor near the front door, window frame, driveway, walkway, backyard, or anywhere you need it. 3. Turn on the receiver and adjust the volume to the correct position. 4. Now the remote sensing system works with infrared sensing technology. 5. Place the receiver in an easily accessible place. 6. When the sensor detects movement, the receiver will emit an audible sound and the LED light will flash. 7. Please wait 30 seconds after turning on the sensor and receiver to activate.