US / Inch - Finished Hex Nuts. These are heavy-duty Grade 8 steel, with zinc-yellow CR+6. Link to all of our matching Yellow Zinc fasteners Available sizes:

1/4"-20

1/4"-28 (Fine)

5/16"-18

5/16"-24 (Fine)

3/8"-16

3/8"-24 (Fine)

7/16"-14

7/16"-20 (Fine)