Want the smoothest richest tone possible from your Mesa 22, Studio 22 or Studio 22 Plus? This kit contains a matched pair of JJ EL84's for the power section. Four Gold Pin ECC83S's for V1 thru V4 and a balanced Gold Pin ECC83S for the phase inverter in V5. 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.