The Movement Detector is a 2013 Nerf N-Strike product. It, as suggested by the name, is a movement detector. It is to be planted in an area, when movement is detected, emits a loud alarm. This is similar to the Electronic Flag in the Dart Tag Capture the Flag blaster set; when the flag is picked up and moved, an alarm plays and the lights iniside the flag pulse back and forth. The Movement Detector, however, has no lights.