AN Bolts

How to read Bolt Sizes The first number after “AN” designates the diameter. The “A” at the very end of all the numbers designates that there will be no hole in the shank. Meaning that the hole is “Absent”. The last number, either single or double digit denotes length; a single digit denotes nominal length to the 1/8th of an inch; double digit numbers denote the first digit as a whole measure in inches, the second an additional nominal sizing to the 1/8 inch measure. Typically, AN hardware this size will have 3/8″ thread length. The abbreviations “FT” = Full Thread. Abbreviations “NF” = Nation Fine thread.