CERTRON FRX I - 1976 - US
Not much information about this company out there... Supposedly, a well known magnetic tape manufacturer based in California since the early 70's, well into the 80's. They produced audio and video magnetic tape in the USA, and eventually also outsourced their end product from Mexico, China and Hong Kong.
NOTE: Only 1 available. Wrapper has multiple blemishes but it's still 100% sealed. The case also has a hairline crack on it on the front (see pic).
USA materials and assembled in Mexico.