This object is a dual triode packaged in a miniature glass envelope with nine pins. It is a digital-service grade similar to the 12AX7 high-mu twin triode with lower gain.
Manufacturer
General Electric Company, USA
Place Manufactured
U. S.
Identifying Numbers
Model number
GL 5751
Printed in white ink around the glass envelope.
Other number
5-13 188-21
Printed vertically in white ink on the glass envelope.