Passage detector alarm, communication range up to 100m (distance between infrared receivers and receiver). The infrared receiver range is 3-7 m. Warns you in advance when guests (or intruders) arrive. Motion detector alarm with 38 ringtones, you can choose the one(s) you prefer! 3 levels of volume adjustment: High or Medium or Low. Working mode of receiver: single LED light flashing or both sound and LED flashing. Power supply (receiver): AC 110-240V. Applications: entry alert, burglar alarm, passage alarm, critter detector, car alarm (indoor), warehouse monitor, closet alarm power supply, garage and tool shed monitor, mailbox sensor, front door or gateway detection.