Aircraft bolt material identification
I have some aircraft bolts that I am trying to use but I don't know what they are made out of. I figured out the last 2 digits are the diameter in 16th's and I think the letter before the last two numbers is the material. I figured out R is titanium but what is L,N,S & T. Thank you.
B30NR14
B30NL16
B30PN12
B30LT12
B30US9