scope:

This commercial item description (CID) covers a personal distress marker light. The personal distress marker light is intended for use as a high intensity visual distress signal by aircrew members who require rescue after an unscheduled abandonment of aircraft. The conditions of rescue may include marine environments. The personal distress marker light is also used by ground personnel for identification and signaling. The distress marker light is capable of transmitting high intensity infrared light in situations where concealment from hostile forces is required.