Tung-Sol Tube Upgrade Kit For Mesa Boogie Mini Rectifier Twenty Five Amps EL84 12AX7 This set includes (2) Platinum (Factory) Matched Tung-Sol EL84 power tubes (4) Tung-Sol 12AX7 pre-amp tubes (1) Balanced Tung-Sol 12AX7 pre-amp tube (phase inverter)