Supports replacing tubes across a wide range of models, including 6J1, 6J2, 6J3, 6J4, 6J5, 6A2, 6K4, 6K5, 6AK5, 6AU6, 6BA6, 6BD6, EF93, 6K7, GE5654, etc. Power supply and compatibility Input power: DC 12 16 V, current 1 A or more. For performance, a DC 12 V supply with 1.5 A is recommended. Power socket: DC 3.5/5.5 mm connector with 21 (specification as provided). Tube information Tube type: 6J3 Note: The tube is supplied disassembled. Key benefits Broad compatibility with multiple common tube types, enabling flexible upgrades and replacements. Simple power requirements using a standard DC supply within the specified range. Clear dependency on a compact power and tube arrangement that supports easy swapping of tubes when needed. The included 6J3 tube is supplied in a disassembled state, allowing inspection or separate installation as part of the setup. Use scenarios DIY tube amplifier projects: easily replaceable tubes to experiment with tonal changes and performance in audio circuits. Equipment or refurbishment: compatible with a variety of tubes to restore devices that use these references. Educational or hobby testing: convenient for learning tube substitution and power requirements in small tubebased modules. Notes The specification list provides the supported tube models and the required power parameters exactly as stated. For results, use a stable DC power source within the 12 16 V range and a current capacity of at least 1 A (1.5 A recommended).