[Herald1360]

The original 2N3055 was a dormant doorstop of a device with lowish Ft and moderate gain along with good second breakdown characteristics. They used non epitaxial construction. The open ended specs, though, meant that cheaper epitaxial devices could easily meet the requirements though they introduced problems for designs that relied on some of the older device's characteristics.

RCA latterly Harris now ? renamed the original device as 2N3055H to distiguish it from epitaxial versions.