Looking for a better tone with more warmth and definition? This is our Standard Retube Kit for the Blackstar Series One 200 Amps. It contains four ECC83S's and a Current Balanced ECC82 for the phase inverter along with a Matched Quad of JJ KT88's for the power section but you can configure this kit to use the JJ 6550's for a slight reduction in power by clicking on the "Customize" button.