M4 Helical Spring Lock Washer from Mexico
A small helical spring lock washer made of carbon steel, designed for M4 metric bolts to prevent loosening from vibration. It features a split ring that compresses under the bolt head or nut, creating tension. Classified under HTS 7318.21.0030 as a non-threaded helical spring lock washer of iron or steel.
Duty Rate — Mexico → United States
55.8%
Rate breakdown
9903.82.0250%Except as provided for in headings 9903.82.14, 9903.85.67 and 9903.85.68, articles of aluminum, of steel or of copper and derivative aluminum or steel articles, as provided for in subdivisions (c)(i)–(v) of U.S. note 16 to this subchapter
9903.05.900%Articles already subject to Section 232 (steel/aluminum/copper + derivatives, autos + parts, wood, medium/heavy vehicles + parts, semiconductors, patented pharma) — U.S. note 52(f)
Import Tips
• Verify steel composition meets HTS iron/steel requirements; provide mill test certificates for customs
• Ensure packaging labels specify 'helical spring lock washers' to avoid misclassification as plain washers