PIR (motion) sensor: PIR sensors are used to detect motion from pets/humanoids from about 20 feet away (possibly works on zombies, not guaranteed). This one has an adjustable delay before firing (approx 2-4 seconds), adjustable sensitivity and we include a 1 foot (30 cm) cable with a socket so you can easily reposition the sensor or mount it using the two drills on either side. Read more.
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