Made in USA by Sylvania.
GB is one of the best seri ever made from Sylvania. 
Most of them are special designed with gold pins for long time to use.
Gold lable version, Black plate, O-Getter. The best of US's 5687 ever made.
Nos in original box. 10 tubes available

Made in Germany by Valvo- Hamburg (1965).
O-Getter, Long gray plate with two silver wings on each side. Looks like ECC802S
Can be used to replace for 12AU7 / ECC82 in some amplifier with low Plate Voltage.
Great sound like Telefunken ECC802S
Nos in original box. Matched pair are available.

Made in USA by Sylvania. 
Fat black plate, D-Getter and copper support.
Gold print, best of 6350 ever made. Great for VTL Amplifier
Nos in original box.
Matched pair and quad are available.

Made in W.Germany by Telefunken. 
Diamond Logo on the bottom, Premium of ECC86.
Super high stableness and low noise. Balanced & detail sounding.

Nos in original box. Matched pair are available.

Made in USA by Bendix.  The 6900 is a version of the 5687 medium-mu triode.
Excellent sounding tube! Also interchanges with the 7044 and 7119 tube. They were used in military radar units and built to extremely high standards. Compatible with Audionote and other quality high end amplifiers.  
Like new and tested very good. No original box.

Made in USA by RCA.
Medium-Mu Triode - Sharp-Cutoff Pentode.
Used in some DYNACO Amplifiers.

Nos in original box. Matched pair are available.

Made in USA by Tung-Sol.
This is other version of 12AU7s tube with 6.3 or 3.15 Volts.
(not 12.3 or 6.3 Volts). All data are the same 12AU7s.
Long gray plate. D-Getter. Very nice sounding tube.
Nos in original box. Matched pair are available.

Made in USA by General Electric.

Gray plate. Copper supports

Nos in original box. Matched pair are available.

Made in USA by Tung-Sol.

Gray plate. Black wall.

Nos in original box. Matched pair are available.