Performance which surpasses NOS original in all areas. Big?? warm and very musical. Superb linearity with a dynamic 3-D sound.</br>Preferred by guitar technicians for re-tubing and upgrading. Equally well suited for HiFi applications</br>Single tube</br>7025/ECC83 equivalent</br></br>Product Description</br></br>Premium high gain Twin Triode with ultra-low microphonic. Improved reissue of the Vintage NOS Tung Sol 12AX7</br><br/>http://www.amazon.com/gp/product/B0018SJLFS