2PCS 6K4 Electronic Tube Valve Vacuum Tube Replacement for 6AK5/6AK5W/6Zh1P/6J1/6J1P/EF95 Pairing Tube Amplifier DIY Preamp Vacuum Tube Replacement for 7-pin 5654/6AK5/6AK5W/6Zh1P/6J1/6J1P tubes. It can directly replace 403A/403B/EF95 and ordinary 5654. And can be used for device that comes with 6J2/6J3/6J4/6J5/6K5 as a replacement. It is fuller, wider soundstage. treble is smoother and bass is clearer and more pronounced while more complex was more defined. High reliability and stability. HiFi and soft sound, low noise. These 6K4 tubes show you difference in natural voice reproduction and simple musical. They sound more clear with an emphasis on clarity, larger soundstage, and bass response is more noticeable. Hear difference, enjoy your . Each package contains a pair of fully tested and matched 6K4 Vacuum Tubes. Note:Replacing wrong type of tube may damage your amplifier. If you are not sure this 6K4 can be used as a replacement for your audio device, please check with your amplifier manufacturer. Specifications: Quantity: 2pcs Package Size: 7.5*5.5*2.5cm / 3.0*2.2*1.0in Material: , Metal Color: Transparent Package Weight: 30g / 1.1oz Type: Electronic Tube Model: 6K4 Package List: 2 * Electronic Tube Each package contains a pair of fully tested and matched 6K4 Vacuum Tubes. These 6K4 tubes show you the difference in natural voice reproduction and simple musical. They sound more clear with an emphasis on clarity, larger soundstage, and bass response is more noticeable. Hear the difference, enjoy your music. Replacement for 7-pin 5654/6AK5/6AK5W/6Zh1P/6J1/6J1P tubes. It can directly replace WE-403A/403B/EF95 and ordinary 5654. And can be used for the device that comes with 6J2/6J3/6J4/6J5/6K5 as a replacement. High reliability and stability. HiFi and soft sound, low noise. It is fuller, wider soundstage. The treble is smoother and bass is clearer and more pronounced while more complex music was more defined.