Hi, can you take this on a plane? I want to use it for a vacation.
Yes. Only items containing CO2 can be of an issue. If you need to carry replacement CO2, you need to check with your airline and most likely check the luggage, not carry it with you.
Does this work for stearns 1339 life jackets?
They work just fine in my Stearns life vest.
Are these the same pins that are in the rearming kit for the M\24 kit for onyx vest?
Yes, exactly the same.
Will these pins work for the onyx m-16 belt pack manual inflatable life jacket?
Yes it does. FYI when I brought them from Amazon out of the pack there were quite a few that were broken.