niceEshop(TM) HC SR501 Human Sensor Module Pyroelectric Infrared Sensor For Microcontrollers Electronic Projects Material:High quality electric part Borad PCB Size:3.7x2.5x2cm(1.46x0.98x0.79inch) Startup Time:2 Seconds to get a measure on room volume Working Voltage :5V(DC)- 20V; Current drain:60uA