Want a very rich and smooth tone with less grit? This is our Gold Pin Option Retube Kit for the Mesa Rectoverb 25 Heads and Combo Amps. It contains six Gold Pin ECC83S's with one being current balanced for the phase inverter in V4. The default power tubes are a matched pair of the JJ EL84's but you can configure this kit to use the JJ EL844's for an earlier breakup by clicking on the "Customize" button!