Automatically sizes all AN bolts up to 5/8" diameter and 5 inches long — slide a bolt in and read the size instantly, no calipers and no guessing. A must-have on the workbench for Affordaplane builders: with dozens of AN3 and AN4 bolts called out in the plans, this $12.50 gauge sorts your hardware pile in seconds and keeps the wrong bolt out of the wrong hole.
