Want a very smooth and rich tone with less grit? This is our Gold Pin Option Retube Kit for the Bogner Metropolis Heads and Combo Amps. It contains a matched quad of JJ EL84's for power, a JJ GZ34 rectifier tube, a single EL84 for the reverb driver along with five Gold Pin ECC83S's one being current balanced for the phase inverter in V3. Just let us know in the comments section if you're looking for an early breakup, a moderate breakup or a later breakup for more headroom in which case we will choose the coolest grades we have available for the power tubes.