Made in USA by RCA.
Balloon type, long engrave base.
One of the great classic triode tubes.
Used but tested excellent as new tube.
Matched pair and quad are available

Made in USA by RCA.
Balloon type, short engrave base.
Similar to 01A, 201A version. One of the great classic triode tubes.
Nos in original box.
Matched pair and quad are available .

Made in USA by RCA.
Silver tube, engrave base. Similar to 01A, 301A in balloon type.
One of the great classic triode tubes.

Nos in original box.

Made in USA by RCA.
The balloon type, engrave base. 
One of the great classic triode tubes
Used but tested excellent.
Matched pair and quad are available.

Made in USA by RCA.
Triode Detector Amplifier tube with 5 VDC filament.
Silver plate. Very good for driver.
Data here
Nos in original box. Matched pair are available.

Made in USA by Raytheon.
Triode Detector Amplifier tube with 5 VDC filament.
Silver box plate, Engrave base.  Bottom Cup-Getter. One of the best 12A ever made. 
Data here
Nos in original box. Matched pair are available.

Made in USA by RCA.
Triode Detector Amplifier tube with 5VDC filament.
Engrave base, silver plate. Very good for driver.
Data here
Nos in box. Matched pair are available.

Made in USA by Arcturus.
Rare version with Blue Glass. Hard to find today
Balloon type. Similar to 26, 226 and 326.
Silver plate. Medium-Mu Direct hearter triode.
Nos in original box. Matched pair are available.

Made in USA by RCA.
Balloon type. Similar to 226 and 326.
Silver plate. Medium-Mu Direct hearter triode.

Like new tubes in good testing. Matched pair are available.

Made in USA by Raytheon.
Balloon type. Similar to 26 and 326.
These are the earliest type with “Raytheon” stamped on the silver box plates.
They are known as 4-pillar tubes.
Nos but no box. Matched pair are available.