Tanner Fasteners Handbook: Understanding Fastener Notation

Building on the basics, this page dives into how fasteners are specified and identified. We’ll break down head styles (hex, pan, flat, etc.), drive types (Phillips, Torx, Allen), and dive into nuts and washers. You’ll also learn how to measure a fastener’s diameter, length, thread count, and pitch – essential knowledge for ordering the right part or matching replacements. With this information, you’ll be able to read a fastener spec like a pro.