PEPCON by H2O, INC. (Track this)
Intl: (009) Electrical and scientific apparatus US: 021 Filing date: 14-Aug-1970 Serial number: 72368103
TOPCON by TOPCON CORPORATION (Track this)
Intl: (009) Electrical and scientific apparatus US: 026 Filing date: 03-Oct-1956 Serial number: 72016917