This is our Standard Retube kit for the Dr. Z Z Wreck Amps. The preamp section uses a JJ Long Plate ECC803S for V1 for a little lower gain with big thick mids and a little more sparkle in the highs. It also includes a matched quad of the JJ EL84 for power, one GZ34 rectifer tube and two ECC83S's, with one of them balanced for the phase inverter in V3.