The Mc Guard is a ceiling-mounted motion detector. It is ideally used in spaces such as offices, apartments, hallways, and staircases. The additional sound activation feature allows for reactivation through noise. The elegant, aesthetically pleasing housing with an integrated lens and invisible buttons prevents unauthorized adjustment of the settings. Superior lens patterns and well-distributed as well as concentrated detection beams provide high sensitivity. In addition to PIR detection, the detector can also be activated by sounds. The ambient lighting can be adjusted for flexible application. The McGuard family now consists of seven different model series, each specialized in its area and functionally coordinated with one another. The devices combine the reliability familiar from Grothe in everyday use with a high benefit in ease of installation and user comfort.