(TT [temper tantrum]) When I started working in engineering if I took a "standards book" out of the bookcase and to my drafting table or even even worse, Xeroxed the page I could have been fired or worse but now days the "blabbering" of Military (et al) fasteners is out there, with limited information, for people to see.
Since people are often using "standards" by name (and number?) as a "slang term" now days then please get it right... for yourself and others. The source and specs is based on the spec's origin such as "AN" (Army Navy) but are they really AN based that spec for fasteners? The number part of the spec or the dia. of the spec then the AN added after it (I am seeing lately is even more omitted but is it the sequential design number for the description of the part design) is not always being used now (is it really a fed design fastener because if the incomplete part number?) but is now more of a slang term w/o meaning (the one I saw yesterday was -8 AN which means nothing). If you are depending on the spec to do it's job it is important that whole the number really is what and is where the specifications are plus the rest of the coding is not even being used which is the second most important part of the number... as a whole.
Example: AN960PD10L (also NAS1149 is, as I remember, is pretty much the same part) is pretty much the standard washer but to break it down: "AN" [Army Navy spec based design] "960" is the sequential spec number, "PD" is the finish, in this case "Plated", 10 is the inside hole dia. in 1/16th of an inch and the "L" says it is a light weight/thin washer. No last letter and the washer is the Standard's standard thickness in the spec. The NAS version is similar.
Most of the international specs are named the same way or a similar based specification I base on what limited use I got into with them (a long story).
I have gotten to the point were the "Grade" now days is even suspect. I have bought what I was told was a certain grade spec part only to have it fail on the first and incomplete tightening.
If you are going to buy a "Spec Part", make sure it is really the spec part, again... not just "blabber". The world is getting so sleazy now days.
Lee
I forgot to mention that US standard fasteners come based on 1/8th of an inch or 1/32 of and inch so the base number in the spec must be known. A dash eight in sixteenths of an inch compared to a dash eight in thirty-seconds of an inch is going to be very different.
Lee