Mastering Massive Passive Retube Kit Version A
This kit is only for Manley MASTERING MASSIVE PASSIVE's with the serial number falling between MMMSMP000 - MMMSMP870. Includes (2x) 5814 or 12AU7 tubes for input, and (4x) 6414 or 12BH7 tubes for driver output. Be aware that some tube brands are subject to change over time and may not match the pictures shown.
UPDATE: We have replaced 6414 tube with 12BH7EH type as of October 2013 on most of our products. There are limited quantities of 6414 GE or RAYTHEON so 12BH7EH is what will ship by default.