VIFLY Finder 2 is a self-powered drone buzzer that can be used on a FPV quad or RC airplane. It comes with light sensor, LED light and loud beeper that could work together to help find a crashed drone. It can still beep loudly even the drone battery was ejected or out of power with a built-in battery. The light sensor will detect light intensity and control the LED light to blink when it is dark. It will automatically enter into sleep mode at night without making noise.
Here is the introducing video: