All of these tubes are practically in new condition. Tubes were for Mesa Boogie Bass 400+, just trying to find my sound. Some I have as back up spares. Will sell whole lot for $200.00 Set of 12 Sovtek 5881- Slightly used- $50.00- Approx. 12 hrs. playing time Set of 12 Mesa STR-430 6L6GC - Very slightly used $90.00 - Approx. 2 hrs playing time. Set of 12 Mesa STR-427 6L6 - 10 used, 2 brand new - $75.00 - Approx. 12 hrs. playing time Set of 4 Mesa Russian#2 12AX7-very slightly used - $20.00 - Approx. 2 hrs. playing time. (noisey) Set of 4 Mesa ECC83 12AX7 - Brand New - $ 35.00 FYI: I have the Svetlana 6L6GC and the 12AX7EH as my chosen sound. Very smooth and clean. Brings out the natural sound of my bass.