Looking for more warmth and definition for you Defender? This is our Standard Retube Kit for the Kustom Defender 15 and V15 Amps. It contains a matched pair of JJ EL84's and a standard ECC83S which is used for both the input and driver tube. A nice upgrade from the stock tubes, sweet and warm! 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.