Section 15 Base metals and articles of base metal 73 Articles of iron or steel 73 18 Screws, bolts, nuts, coach screws, screw hooks, rivets, cotters, cotter pins, washers (including spring washers) and similar articles, of iron or steel 73 18 13 - - Screw hooks and screw rings Commodity Code Description 73 18 13 00 - - Screw hooks and screw rings