18-Pitch  inserts are available in both locking and free-running varieties. These inserts are commonly used in sizes from 1 inch up to 5 inches in diameter. Regardless of the diamater, they all share the same 8 threads per inch. The standard material for these inserts is 18-8 stainless steel, but they are also available in Inconel X750. These inserts can also be plated in Dry-Film Lube, or coated in Silver. Our inserts are DFARS compliant, and conform to military or aerospace specifications when applicable.