I mailed them on a day that the post office was closed so I used the automated postage thingie.
Since I have received many bubble mailers with "large letter" postage, I thought would try it. The postage on three chips was, if I recall, $1. If I take the same package to the counter, it costs $1.34 (ish). I know that a single chip costs me $1.17 to mail if I go to the counter.
Anyway, if the package arrived with postage due, please let me know and I will make it right. If it arrived without postage due I guess I'm done with taking bubble mailers to the counter at the post office.