Sylvania 6SN7W - early black plates, chrome dome

This 1951 Sylvania 6SN7GT tube has a medium bottle, bottom getter, and early black plates with 2 rivets. The full black base has green print with the Sylvania lightning logo. Tube tests as new with balanced sections and very low noise.

The 1960s Sylvania 6SN7GTB tubes in this precisely matched pair have black plates and lots of chrome flashing. The yellow print on the bases has the Sylvania lightning logo. Both tubes test as new and are matched for both current draw (mA) and Gm.