Importers of HS 4421.99 (spring-type) from Vietnam actually paid 12.19% on the taxed portion of the value in 2026-06 — 12.19% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is 6.5¢/gross. Over the window the rate on the taxed portion moved 3.33% → 12.19%, with the largest single step -8.9pp in 2026-03. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. Collected 12.19% against an HTS base of 6.5¢/gross. Reproduce exactly: tariff_story(hs: "4421.99", origin: "Vietnam") · see it at trimtabist.com/tariffs
HS 4421.99. The schedule base rate is 6.5¢/gross; importers from Vietnam actually paid 12.19% on the dutiable value in 2026-06. Measured, not modelled.
Over the window the collected rate moved 3.33% (2023-07) → 12.19% (2026-06), largest single step -8.9pp in 2026-03.
Vietnam's lower duty (12.19% vs 31.96%) lets it price up to 17.6% above China at the factory and still match on duty-inclusive customs cost. But on the LATEST measured prices, China actually lands cheaper — $1.48/kg vs $1.83/kg (duty in, freight out).
All goods from Vietnam · the whole tariff ledger · 48 CBP rulings cite this code · reproduce: tariff_story(hs: "4421.99", origin: "Vietnam") via /connect. Not customs or legal advice.