4  vintage tubes double triode 12AX7 (=ECC83)  from ADZAM (Philips).
The factory code symbol  ≠ at the bottom indicates that the tubes were made at Siemens und Halske (München) in 1955  (tube number 2 and 3 in July and tube number 1 in August). Type code is mCP. 

Long plates 17mm.

Tubes 1,2,3 :silk screen is partially  wiped off, mfrs code at the bottom is readable

Tube 4 : silkscreen wiped off, code partially visible. Otherwise, physical appearance similar to the other 3 tubes (internal structure and  on top of the glass 4 seams in a cross).

Price is for 4 pieces.

The tubes are used and have been tested. They are sold as is as  pictured without any warranty expressed or implied.

Test conditions
Va=250V Vg=-2V
Nominal values : Ia=1.2mA – S=1.6mA/V

Test results:

Tube #
Triode 1(pins 1-2-3)  Ia - S
Triode 2 (pins 6-7-8) Ia - S

#1
1.2mA – 1.8mA/V
1.3mA – 1.9mA/V

#2
1.2mA – 1.6mA/V
1.2mA – 1.6mA/V

#3
1.2mA – 1.6mA/V
1.1mA – 1.5mA/V

#4
1.1mA – 1.6mA/V
1.1mA – 1.5mA/V

Standard shipping with Bpost to EU with track and trace is €35.

Private sale - no returns