First Airmail Flight Cachet

I found this in my grandparents' papers, along with its letter from the postmaster (a family friend). I'm wondering if it has value for anyone and what to do with it.

Personally, I would be saving this in my family's genealogy history folder
to pass on to children.

I agree. Such covers generally sell for $5-10 unless there is something "special" about them.

Hello MJDW. Your cover represents a very large part of air mail collecting. The American Air Mail Society has hundreds of members including me and many publications on the topic of commercial air mail routes and your cover (envelope) lists it as CAM 99 I believe (hard for me to see). Consider going to our website and becoming a member. The other comments are also helpful.

How about you or another family member?

My father, eventually a postmaster himself, collected first day covers (envelopes with the stamp used being used on the very first day it was being officially sold by the USPOD). While I too am a stamp collector, I have little interest in first day covers of that era which have little monetary value similar to your item. EXCEPT they have great value to me as they document the various addresses at with I lived throughout the City of Berkeley CA between being brought home from the Berkeley hospital until the house in an adjoining city was purchased a couple of years later with an address I can remember and at which my parents were still living when they each passed from old age. I moved more arriving at the house than my two moves leaving the house.