SMAKN 5 PCS Ceramic Gold Plated 9pin B9A PCB Mount Tube Socket for 12AX7/ECC83/12AT7/6DJ8 gold plated 9 pin B9A tube sockets For 12AX7/ECC83/12AT7/6DJ8/B339/CV492/6L13 Working Voltage:1500V Contact Resistance&gt;0.01 OHM Insulation Resistance &lt;10000Mohm