PIR-2-Pi IR Motion Detector - PIR Infra Red Movement Sensor & GPIO clip for Raspberry Pi 3, Pi 2, B+, A+, B and A models. Connects directly to GPIO pins. PIR module sends signals on GPIO4.
Get some free detection shell scripts to use with this adapter by looking at the preview pages here: http://www.amazon.com/dp/B00N5RRUJY