If you travel to places where you might want people searching
for you from the air to notice you amid many square miles of search area,
a signal mirror is remarkably effective.
https://adventure.howstuffworks.com/survival/gear/use-signal...
PLB or satellite messengers will not only let the first responders know where you are (both by transmitting your location via satellite distress signal as well as using 121.5 MHz 'homing signal' in the case of PLBs to help first responders find your exact location), but also trigger the SAR operation rather than waiting for someone to notice you've been gone for too long.
With the beacon they'll know exactly who and where you are (but nothing about the nature of the problem) and it also transmits a homing signal for aircraft. With the inReach if you just trip the SOS they only get who and where, but you also have text messaging so that you can communicate how urgent the situation is and what it will take to get you out. (Safe but unable to extract won't get anything like the response that femoral artery severed, tourniquet applied gets.)