Importers of HS 8544.70 (optical fiber cables) from Korea, South actually paid 9.53% on the taxed portion of the value in 2026-06 — 9.3% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is Free. Over the window the rate on the taxed portion moved null% → 9.53%, with the largest single step +13.9pp in 2026-01. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. The HTS base rate is Free — importers actually paid 9.53%, so the trade-war overlay added 9.5 pts, measured at the border (not a summed rulebook estimate). Reproduce exactly: tariff_story(hs: "8544.70", origin: "Korea, South") · see it at trimtabist.com/tariffs
HS 8544.70. The schedule base rate is Free; importers from South Korea actually paid 9.53% on the dutiable value in 2026-06 — the trade-war overlay added 9.5 points, measured at the border. Measured, not modelled.
Over the window the collected rate moved % (2023-07) → 9.53% (2026-06), largest single step +13.9pp in 2026-01.
Korea, South's lower duty (9.3% vs 26.25%) lets it price up to 15.5% above China at the factory and still match on duty-inclusive customs cost. But on the LATEST measured prices, China actually lands cheaper — $71.28/kg vs $108.11/kg (duty in, freight out).
2 Chapter-99 measures name Korea, South; scope mapping is partial (several annexes are PDFs) — absence never means exemption. They do not sum, and some are product-specific — the collected rate above is the composed truth.
All goods from South Korea · the whole tariff ledger · 5 CBP rulings cite this code · reproduce: tariff_story(hs: "8544.70", origin: "South Korea") via /connect. Not customs or legal advice.