Tung-Sol Gold 12AX7 / ECC803S， Matched Quad<div style="text-align: left;"><strong>[Product Information]</strong><ul><li><span class="a-list-item"> Matched Quad </span></li><li><span class="a-list-item"> Matched for both gain and conductance </span></li><li><span class="a-list-item"> Dynamic 3-D sound </span></li><li><span class="a-list-item"> High gain and ultra-low microphonics </span></li><li><span class="a-list-item"> Gold pins </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/511N9PHH1tL.jpg" noproxy>