How are US tariffs on imported LED lamps calculated?

Base tariff: 2% (LED lamps, HS 8539.52.00) to 8% (LED fixtures, HS 9405.31.00).

Additional tariff: Section 301 imposes an additional 7.5% to 25% (depending on product type).

Avoidance strategy: Re-exporting through Vietnam or Mexico can reduce the tariff; a certificate of origin is required.