Type
Inscription, Makers MarkLocation
On the back of the device.Transcription
Na-Ald
Cogswell
Condenser
Alden MFG.CO
SRFLD MASS.Language
EnglishMaterial/Technique
EngravedType
Inscription, Makers MarkLocation
On the backside of each headphone.Transcription
C. Brandes Inc.
New York
Superior
+
"Matched Tone"
Trade Mark Reg. U.S. Pat. OFF
Made in U.S.A.
Pat PendingLanguage
EnglishMaterial/Technique
Engraved