Features / Description of Product: Wireless Design, easy to install. Unit utilises PIR motion sensor technology for detection and alert purposes. Strong sensitivity and anti-interference technology, it can effectively detect human movement within its indoor effective range and angle. PIR motion sensor with blue flashing indicator light. Technical Specifications: Greeting Melodies: 11 Languages of ‘Hello, Welcome’, 2 music melodies and 1 alert alarm for your selection. Sensor Distance: Up to 7 meters Sensor Angle: Approximately 120 Power Supply: USB Port: 5VDC 2A (USB Cable NOT included) Battery: 3 x AAA 1.5V (Battery NOT included) Model: VC-88 Packing Dimension: L15.2 cm x W5 cm x H22.1 cm Weight: 0.15 KG