The Bosch DS150i is a request-to-exit motion detector designed for use in access control systems. It uses passive infrared motion sensing to detect a person approaching a secured door from the inside and signals the access control system to unlock or release the door. The device is intended for indoor use and can be mounted on a wall or ceiling above or near the door. It features adjustable relay timing, visible activation indication, and selectable fail-safe or fail-secure operation. The DS150i is commonly used in commercial and industrial buildings to provide safe and convenient exit from secured areas without the need for keys or credentials.