EF86 High-Frequency Pentode Triode from Mexico
The EF86 is a high-gain pentode vacuum tube used as the first audio stage in classic guitar amplifiers. Classified under HTS 8540.89.00.40 for its multi-electrode thermionic construction equivalent to triode-pentode functionality. Renowned for warm overdrive tone.
Duty Rate — Mexico → United States
13.7%
Rate breakdown
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• Include microphonic testing results as these tubes are sensitive to vibration in amplifier use
• Specify B9A noval base construction to distinguish from subminiature or acorn tubes
• Provide transconductance specifications confirming high-mu pentode characteristics