Finished hex nuts are the most widely used nuts and will work for most applications.
1 & ASTM F467.Size: 1/4 inch-20Most commonly used and versatile nutFinished nuts are six sided nuts of standard thickness vs heavy duty hex nutsScrews onto a bolt, cap screw or threaded rod of the same thread sizeUse with washers to help distribute the load (not included)Thread Type: Coarse, Thread Class: UNC-2ASpecification(s) Met: ASME B18.2.Hex Nut, 1/4"-20, Aluminum, Not Graded, Aluminum, 25 PK They are standard thickness and can be installed with a wrench or socket tool.