UNC

UNC (Unified National Coarse) threads are the most common American imperial thread standard for general-purpose fasteners. Known for their robust, deep thread form, UNC threads provide strong, durable connections that are less prone to cross-threading and are easy to assemble and disassemble. 

Key Characteristics

  • Thread Angle: UNC threads use a 60° symmetrical V-profile flank angle, the same as modern metric ISO threads.
  • Designation: They are designated by their nominal major diameter (in inches) and the number of Threads Per Inch (TPI). For example, a 1/4"-20 UNC thread has a 1/4-inch diameter and 20 threads per inch.
  • Pitch: They have a larger pitch (fewer threads per inch) compared to the Unified National Fine (UNF) series.
  • Tolerances: The coarse pitch allows for greater tolerances in manufacturing and plating processes and makes them more tolerant of slightly dirty or damaged threads.
UNC
A2 STAINLESS

A2 STAINLESS
A4 STAINLESS

A4 STAINLESS