Nagra IV-SJ was a professional portable open-reel stereo
tape recorder,
introduced in 1972 by Nagra Kudelski
in Chesaux-sur-Lausanne (Switzerland).
Aimed at audio professionals, it was very popular within
the broadcast and film industry. The device was also used by
law enforcement and intelligence agencies
for wire tapping, interrogations and for
covertly recording
of suspects.
